Histology and histopathology Vol.13, nº 3 (1998)

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Open Access
Endothelin-l enhances thymocyte proliferation in monolaterally adrenalectomized rats with contralateral adrenocortical regeneration
(Murcia : F. Hernández, 1998) Malendowicz, L.K.; Macchi, Verónica; Brelinska, R.; Trejer, M.; Gottardo, Giuseppe; Nussdorfer, G.G.
Endothelins (ETs) are a family of vasoactive peptides widely distributed in the body systems, where they exert pleiotropic biological effects, acting through two main subtypes of receptors, named ETA and ETB. Evidence indicates that ET-1 plays a permissive role in the development of neural crest-derived structures, among which are the epithelia1 cells of the thymus. These cells are known to control proliferation and differentiation of thymocytes, a process requiring adequate levels of glucocorticoids. Therefore, we have investigated the effects of ET-1, that binds both ETA and ETB receptors, on thymocyte proliferation in monolaterally adrenalectomized rats with contralateral enucleated adrenal at day 4 and 8 of regeneration, when glucocorticoid production is very low and, respectively, rather normal. Metaphase index (percentage of metaphase arrested cells) of thymocytes is the lowest at day 4 of regeneration, and markedly rose at day 8, thereby confirming the need of sizable levels of circulating glucocorticoid for the maintenance of a normal rate of thymocyte proliferation. ET-l markedly increased the mitotic index of thymocytes at both times of adrenal regeneration. At day 8 of regeneration, the ETA-receptor antagonist BQ-123 markedly lowered mitotic index of thymocytes, and annulled its ET-1- evoked raise. Conversely, the ETB-receptor antagonist BQ-788 was ineffective. Collectively, these findings clearly indicate that endogenous ETs, through the activation of ETA receptors, are involved in the maintenance and stimulation of thymocyte proliferation in the adult rat, thereby playing a possibly important role in the modulation of the immune-system functions.
Open Access
Histochemical study of skin and gills of Senegal sole, Solea senegalensis larvae and adults
(Murcia : F. Hernández, 1998) Sarasquete, C.; Gonzalez de Canales, M.L.; Arellano, J.M.; Muñoz Cueto, J.A.; Ribeiro, L.; Dinis, M.T.
A battery of horseradish peroxidaseconjugated lectins (Con A, WGA and DBA), as well as conventional histochemical techniques (PAS, saponification, Alcian Blue pH 0.1, 1, 2.5, chlorhydric hydrolisis, neuraminidase, Bromophenol blue, Tioglycollate reduction and Ferric-ferricyanide-FeIII) were used to study the content and distribution of carbohydrates, proteins and glycoconjugate sugar residues on the skin and gills of Senegal sole, Solea senegalensis larvae and adults. During larval development of Solea senegalensis (from hatching until day 45 posthatching), epidermal sacciform, as well as branchial and epidermal chloride cells were unreactive with all cytochemical tests performed in this paper. Mucous or goblet cells of the corporal skin and gills containing strongly sulphated acid glycoproteins were evident on days 15-20 of larval development, as well as in epidermal and branchial mucous cells of adult specimens, which also contained GlcNAc andlor sialic acid. In adult specimen, the proteic content was higher in branchial mucous cells than in epidermal cells. In larvae, variable amounts of glycoproteins containing sialic acid, GlcNAc, GalNAc, Man andlor Glc residues were observed in epithelia1 cells and/or cuticle. GlcNAc andlor sialic acid sugar residues were only weakly detected in glycoproteins of some epidermal and branchial mucous cells of larvae by day 45, because from hatching until metamorphosis, lectin reactions (WGA, Con A and DBA) were negative in mucous cells.
Open Access
Liver cell dysplasia: reactivities for c-met protein, Rb protein E-cadherin and transforming growth factor-01 in comparison with hepatocellular carcinoma
(Murcia : F. Hernández, 1998) Zhao, M.; Zimmermann, Astrid
In the present retrospective study, liver cell dysplasia (LCD) occurring in cirrhotic livers associated or not associated with hepatocellular carcinoma (HCC) was immunohistochemically analyzed for the expression of hepatocyte growth factor receptor (c-met protein), Rb (retinoblastoma gene) protein, E-cadherin, and transforming growth factor-B-l (TGF-B-1). Cytoplasmic cmet protein staining was observed in about half of the HCC's, and its prevalence was about twice as high in high grade vs. low grade tumors, but it was not correlated with proliferative activity as based on PCNA labelling. In LCD, reactivity for c-met protein was restricted to the small cell type. Nuclear staining for Rb protein was found in HCC's, and was not related to type, grade or proliferative activity, whereas no immunoreactivity was observed in normal, hyperplastic or dysplastic hepatocytes. Expression of E-cadherin prevailed in HCC's of lower grade, and particularly in those with a trabecular or acinar growth pattern. Ecadherin staining was detectable in normal and large dysplastic hepatocytes, but not in small dysplastic liver cells. TGF-B-1 reactivity was observed in more than half the HCC's, but not in normal or dysplastic hepatocytes. These findings underline the phenotypic difference between large cell and small cell liver dysplasia, and support the hypothesis that small cell dysplasia is a precursor lesion in a hepatocarcinogenic pathway.
Open Access
Importance of interfacial water in permeabilization of ceramide bilayers
(Murcia : F. Hernández, 1998) Neitchev, V.; Kostova, E.; Dimitrov, A.S.
The role of structured water at the membrane- aqueous interface in regulating the water permeability functions of the epidermal horny layer (Stratum corneum) is not clear at present. The subject of this review is the effect of perturbed interfacial water structure on the relative water permeability properties in shrinkage experiments of reconstituted vesicle suspensions of ceramides and cholesterol in the gel phase. Water structure was perturbed by a series of reagents known to affect the phase equilibrium of lipid assemblies. Multilamellar bilayers containing synthetic ceramides N-palmitoyl-D-L-dihydrosphingosine, and Noleoyl- D-sphingosine were used as model membranes. The reagent binding to the ceramide membrane was determined by fluorescence measurements with 1- anilino, 8-naphtalene sulphonate (ANS). A dependence of number of binding sites for ANS on the type of reagent was found. The change of relative water permeability with concentration of reagents was studied. Analysis of these data reveals that the anomalous behaviour of relative water permeability with the concentration of reagents used is due to concentrationdependent structural transitions of the bound water at the membrane-aqueous interface. Different possibilities of interaction of the reagents with the interface are discussed. At the end, it is suggested that the interfacial water in multilamellar ceramide structures may also contribute to the water holding and permeability barrier functions of cell membrane complex within the stratum corneum.
Open Access
Genetics and pathology of voltage-gated ca2+ channels
(Murcia : F. Hernández, 1998) Ophoff, R.A.; Terwindt, G.M.; Ferrari, M.D.; Frants, R.R.
Neurotransmitter release, neuronal excitation, and a whole variety of other neuronal functions are controlled by the intralextra cellular ca2+ gradient. The major pathway for entry of ca2+ into the excitable cells is mediated by voltage-gated ca2+ channels. Several functional subclasses of voltage-dependent ca2+ channels have been identified, based on their pharmacological, biophysical properties, and molecular cloning. Recently, three human diseases (familial hemiplegic migraine, episodic ataxia type 2, and spinocerebellar ataxia 6) were added to the growing list of ion-channel disorders, all caused by different mutations in the P/Qtype ca2+ channel a1 subunit. Molecular analysis of the ca2+ channelopathies will provide new insights into the role, function and pathology of these voltage-gated ca2+ channels.
Open Access
Phenotypic modulation of smooth muscle cells during formation of neointimal thickenings following vascular injury
(Murcia : F. Hernández, 1998) Thyberg, J.
Smooth muscle cells build up the media of mammalian arteries and constitute one of the principal cell types in atherosclerotic and restenotic lesions. Accordingly, they show a high degree of plasticity and are able to shift from a differentiated, contractile phenotype to a less differentiated, synthetic phenotype, and then back again. This modulation occurs as a response to vascular injury and includes a prominent structural reorganization with loss of myofilaments and formation of an extensive endoplasmic reticulum and a large Golgi complex. At the same time, the expression of cytoskeletal proteins and other gene products is altered. As a result, the cells lose their contractility and become able to migrate from the media to the intima, proliferate, and secrete extracellular matrix components, thereby contributing to the formation of intimal thickenings. The mechanisms behind this change in morphology and function of the smooth muscle cells are still incompletely understood. A crucial role has been ascribed to basement membrane proteins such as laminin and collagen type IV and adhesive proteins such as fibronectin. A significant role is also played by mitogenic proteins such as platelet-derived growth factor (PDGF) and basic fibroblast growth factor (bFGF). An improved knowledge of the regulation of smooth muscle differentiated properties represents an important part in the search for new methods of prevention and treatment of vascular disease.
Open Access
lmmunohistochemical detection of metallothionein in liver, duodenum and kidney after dietary copper-overload in rats
(Murcia : F. Hernández, 1998) Mullins, J.E.; Fuentealba, I.C.
Metallothionein (MT) has been used in immunohistochemical techniques to indicate presence and distribution of heavy metals within biological tissues. This study describes a comparison of the pattern of MT-immunostaining in the liver, duodenum and kidney during dietary copper overload in rats. Sixteen male 10-week-old Wistar rats were randomly allocated into groups of four. Two groups were fed a pelleted diet containing 1,500 mgíkg copper and two control groups received a rodent diet containing 10 mgkg copper. After 6 weeks samples of liver, kidney and duodenum were collected for immunohistochemistry and histology. An indirect immunoperoxidase technique, using monoclonal antibody E9 against horse MT and polyclonal sera against rabbit MT, was employed. Copper-loaded rats had marked MT-immunoreactivity within the nucleus and cytoplasm of many periportal hepatocytes, renal proximal convoluted tubule epithelial cells, intestinal columnar epithelial cells and Paneth cells. Immunohistochemical staining was similar using either mouse anti-MT polyclonal serum, or monoclonal antibody E9. Hepatocytes surrounding inflammatory foci were positive for MT, supporting the proposed role of this protein in free radical scavenging. The presence of MTexcretion o€ copper-metallothionein (Cu-MT) in copperloaded rats. Paneth cells were easily detected using MTimmunostaining. MT may play a part in absorption of copper from intestinal contents and possible storage as CU-MT in Paneth cells. The function of Paneth cells remains unknown but the presence of marked MTimmunoreactivity in these cells, observed in copperloaded rats, suggests their involvement in homeostasis and metabolism o€ copper. in the kidney appears to be associated with renal
Open Access
Preservation of human skin structure and function in organ culture
(Murcia : F. Hernández, 1998) Varani, J.
Human keratinocytes can be maintained in monolayer culture under serum-free conditions for an extended period of time. Under low ca2+ conditions (e.g., 0.05-0.15 mM), an undifferentiated state is maintained and the cells proliferate optimally. When the ca2+ concentration is raised to approximately 1.0 mM, differentiation occurs and growth slows. Human dermal fibroblasts can also be maintained in monolayer culture under serum-free conditions, but in contrast to keratinocytes, a physiological level of extracellular ca2+ (above approximately 1.0 mM) is required. A variety of growth factors stimulate roliferation of both cell types but do not replace the CaP+ requirement of the fibroblast population. All-trans retinoic acid also promotes proliferation of both cell types and, most interestingly, replaces the requirement for a physiological level of ca2+ in the fibroblast cultures. Human skin can be maintained in organ culture for an extended period of time under serum-free conditions. Conditions optimized for fibroblast proliferation (either physiological ca2+ or all-trans retinoic acid) are required. In the presence of culture conditions optimized for the epithelial cell component, both the epidermis and dermis rapidly lyse. These data suggest that the fibroblast is the critical component in maintaining homeostasis of skin, and that maintenance of the epidermis as well as the dermis depends on the viability and functioning of these cells.
Open Access
A three-dimensional study of human fetal endocervix with special reference to its epithelium
(Murcia : F. Hernández, 1998) Barberini, F.; Makabe, S.; Motta, P.M.
The development of human fetal cervix has been systematically studied by SEM, obtaining a detailed map of its fine structure, particularly concerning the differentiation and maturation of the endocervical epithelium, including its "eversion" and "squamous metaplasia", normally occurring in postnatal life, but not yet observed in detail by electron microscopy in the fetus. Cervices from spontaneous abortion at 12, 15, 18, 20, 21 and 22 weeks and from intrauterine fetal death (hydrocephalus) at 31 weeks of development have been examined. At 12-15 weeks, as the canalization of the cervix proceeded, the endocervical epithelium consisted of high polyhedral cells, with regularly flattened or concave apices exhibiting scarce microvilli and often single primary cilia. Some narrow intercellular infoldings probably corresponded to primordial tubular glands. At the 18th week the epithelium was made up of a mosaic of flat or slightly raised polygonal cells, whose apical surface showed thin microplicae. At the 20th week a pseudostratified epithelium with many apically convex cells lined the cervical canal and the tubular glands. At 21 and 22 weeks "plicae palmatae" developed, covered by cells, often showing a smooth central area surrounded by microvilli, provided with a primary cilium and swollen by secretory material. This also formed rounded masses on the epithelium. In the lower part of the endocervix some very elongated cells showed short microplicae resulting from fusion of microvilli. At the 31st week secretion increased and its products spreading from the bottom of the glands contacted isolated ciliated cells at their openings and diffusely covered the surface epithelium. Most of the ectocervix exhibited squamous elements, with welldeveloped labyrinthine microplicae. These cells could overlap each other and also desquamate. The zone of the portio vaginalis around the OS of the cervical canal appeared infolded and hypertrophic. Here, an indented squamo-columnar junction between the ectocervical and endocervical epithelium, caused by tongue-like prolongations of squamous epithelium directed toward the endocervix, was found. Their tips consisted of elongated cells, rich only in short microvilli. Our data indicate that the features of the microvillous cells are an expression of a hormone-dependent differentiative process. Thus, their secretion might be stimulated by progesterone. Similarly microplicae on the ectocervical epithelium (a sign of squamous maturation) might be promoted by estrogens. Furthemore, two aspects were significative: 1) the finding - in an early phase only (18th week) - of endocervically-located squamous cells, although devoid of microplicae; and 2) the occurrence - in the latest phase (31st week) - of an indented squamo-columnar junction on the surface of the portio. These features are in agreement with the caudal shift of the squamo-columnar junction near the uterine cavity to the ectocervix after cervico-vaginal demarcation; the squamous metaplasia of this everted endocervical epithelium has been reported by some authors. It is likely that these processes, occurring in fetal life as well as in pregnant women, are related to a common hormonal background, arising from the mother to her fetus.
Open Access
Glutamate-like immunoreactivity in axon terminals from the olfactory bulb to the piriform cortex
(Murcia : F. Hernández, 1998) Hennequet, L.; Gondra, J.; Sendino, J.; Ortega, F.
A highly specific anti-glutamate monoclonal antibody, mAb2D7, was used together with light and electron microscopy to elucidate the role played by the amino acid glutamate in the projection from the olfactory bulb to the piriform cortex in the rat. By light microscopy, glutamate-like immunoreactivity was observed in neuronal cell bodies and in the neuropil of the piriform cortex. Double labelling experiments which involved injections of wheat germ agglutinin-horseradish peroxidase into the olfactory bulb and a postembedding immunogold method for electron microscopy revealed anterogradely labelled terminals making asymmetric synaptic contacts on dendrites in the piriform cortex which contained high levels of glutamate as assessed by quantification. These results further support a role for glutamate as a neurotransmitter in the efferent pathway of the rat olfactory bulb.
Open Access
Cellular proliferation in the rat pineal gland during postnatal development
(Murcia : F. Hernández, 1998) Carvajal, J.C.; Carbajo, S.; Gómez Esteban, M.B.; Alvarez-Morujo, A.J.; Muñoz Barragan, L.
To establish a possible correlation between the rate of cellular proliferation and already documented functional and morphological characteristics of the rat pineal gland during postnatal development, the bromodeoxyuridine labelling method was used to evaluate the fraction of cells at the S phase of the cell cycle in paraffin sections from I-, 7-, 14- and 28-day-old rats. Numerical density, taken as an indirect measure of cell hypertrophy, was also evaluated. During the first week after birth the percentage of S phase-cells in the rat pineal gland sharply decreased from around 9% to 1.3%. A smaller but also significant decrease was found from the 7th to the 14th postnatal day where S phase cells were less than 0.5% of all pineal cells. A very low percentage was also seen in samples from 28-day-old rats. Numerical density, namely, the total number of cells per surface unit of pineal section, decreased from birth to the end of the first month. This decrease was also steeper from birth to the 7th postnatal day than at any other period of the study. These results support the idea that a strong expansion of the cellular population of the rat pineal gland precedes morphological and functional maturation and opens the way to further exploration of the relationship between functional and proliferative responses of the pineal gland.
Open Access
Ultrastructural study of the clearance of intracerebrally infused native and modified albumin-gold complexes
(Murcia : F. Hernández, 1998) Dobrogowska, D.H.; Lossinsky, A.S.; Vorbrodt, A.W.
The main objective of this ultrastructural study was to gain a better understanding of the involvement of brain vasculature in clearance of proteins from edematous fluid. For this purpose, both native and modified (cationized, glucosylated, and mannosylated) bovine serum albumin-gold complexes (BSA-G, catBSA-G, glucBSA-G and manBSA-G respectively) dissolved in phosphate-buffered saline (PBS) were infused (10 pl) into mouse cerebral cortex. Samples of brain were taken at 30 min, 1 h, and 24 h post-infusion for electron microscopical examination. All BSA-G complexes were rapidly taken up and deposited inside the cytoplasm of pericytes and of various glial cells (microglia and eventually astrocytes) located in the area adjacent to the infusion site. Only glucBSA-G particles also appeared inside the nuclei of some cells. In the applied experimental conditions and at the examined time intervals, neither BSA-G nor catBSA-G and glucBSA-G complexes were transported back to the bloodstream, although they entered vascular basement membrane and were eventually internalized in the endosomes or multivesicular bodies of the endothelial cells. Only a few gold particles representing the manBSA-G complex were found inside the vascular lumen, suggesting their reverse transport to a rather small degrce. The mechanism of this transport, however, remains unclear. Complexes of catBSA-G were apparently trapped by the negatively charged vascular basement membrane and remained in this structure without any further significant uptake by the endothelial cells. These observations suggest that large size and multimeric nature of albumin-gold complexes are limiting factors making it difficult to interpret the results and hampering their relevance to the clearance in vivo of native albumin from brain edematous fluid.
Open Access
Lectin binding in the human endometrium in early luteal phase following controlled ovarian hyperstimulation
(Murcia : F. Hernández, 1998) Gheri, G.; Gheri Bryk, S.; Taddei, G.; Borri, P.; Noci, I.
A lectin histochemical study was performed to investigate the glycoconjugate saccharidic moieties on the endometrial epithelium and stroma in 12 women undergoing controlled ovarian hyperstimulation (COH) for in-vitro fertilisation for embryo transfer (IVF-ET) in early luteal phase. 7 control subjects were also evaluated. For this purpose a battery of seven horseradish peroxidase-conjugated lectins (PNA, SBA, DBA, WGA, ConA, LTA and UEA I) was used. Cytochemical controls were performed for specificity of lectin-sugar reaction. As far as the endometrial glands and stroma are concerned, the obtained data showed no differences in the endometrial lectin binding between the subjects of the control group and the ones undergoing COH, with the exception of PNA reactivity at the level of the apical portion of the glandular cells, which was detected only in COH women. It is noteworthy that, although the endometrial dating using the Noyes's criteria showed marked dissynchronies between the stroma and the glands in COH subjects, a uniformity of lectin binding, revealing the same type and localization of terminal oligosaccharides, was observed in all the examined subjects. The uniformity in distribution of the sugar residues detected in the endometrial specimens following COH might be due to the massive FSH and/or hCG treatment which probably determines an endometrial environment almost equal in all the examined subjects. In all the treated subjects reactivity with sialidase-WGA and ConA, revealing the presence of Nacetyl -D-glucosamine and D-mannose respectively, was detected at the level of the lining epithelium.
Open Access
Effects of ischaemia-reperfusion and cyclosporin-A on cardiac muscle ultrastructure
(Murcia : F. Hernández, 1998) Jurado, F.; Bellón, J.M.; Pareja, J.A.; Golittsin, A.; Millán, L.; Pascual, G.; Buján, J.
The present study investigates the effects on the cardiac muscle cell of two of the determining factors for the success of organ transplant; ischaemia-perfusion and immunosuppressive treatment with cyclosporin-A (CsA). To this end an abdominal, heterotopic heart transplant model in singenic Sprague-Dawley rats was employed. Three study groups were established: Group I (control, n=15) animals undergoing heart transplant without treatment; Group I1 (n=15) animals undergoing heart transplant and subjected to a daily dose of CsA in a cremophor vehicle (sandimunB) (5 mg/kg/sc); Group I11 (n=15): animals undergoing heart transplant and administered a daily dose of pure CsA (5 mg/kg/sc). Recipient animals were sacrificed 7, 14, 21, 30 and 50 days after transplant. During the post-operative period, heart function was assessed by daily abdominal palpation. Graft specimens obtained at each follow-up period were subjected to light and transmission electron microscopy. Immunohistochemical analysis of specimens was performed using the rat macrophagespecific monoclonal antibody MCA-341. The ischaemia/reperfusion process induced considerable alteration to cardiac muscle cells of control animals. Effects, apparent after the first week of transplant, included mitochondrial swelling and loss of cristae, hypertrophy of the sarcoplasmic reticulum and structural changes to sarcomeres. Two weeks after transplant, the myocardium was infiltrated by inflammatory cells. These effects diminished 30 days post-transplant. Cardiac tissues of treated animals (groups I1 and 111) showed similar behaviour although, in the latter group, mitochondrial damage was greater and intense myocardial fibrosis took place. Infiltration of cardiac muscle by white blood cells did not take place until 3 weeks post-implant. These results indicate: a) The ultrastructural changes detected in cardiac fibres of animals of the three study groups were attributable to the ischaemialreperfusion process rather than to treatment with CsA; b) CsA appears to augment mitochondrial damage and myocardial fibrosis; c) the inflammatory response was delayed and reduced by the immunosupressant; and d) the cremophor administration vehicle did not seem to exert an independent toxic effect on the myocardium.
Open Access
Oxidative stress and amyloidosis
(Murcia : F. Hernández, 1998) Ando, Yukio; Suhr, O.; El-Salhy, M.
From recent findings concerning free radical injury in several types of amyloidosis, it appears that free radical injury is involved either amyloid formation or in post-fibrillar modification. As we show in this review, among the more than 20 different types of amyloidosis, only a few types of amyloidosis present direct evidence of free radical involvement in amyloid formation. However, if we search further for other types of amyloidosis, other important information on free radical injury may be forthcoming. Free radical injury is probably central for the toxic properties of amyloid deposits.
Open Access
Effects of octreotide on propylotiouracil-induced goiter in rats: a quantitative evaluation
(Murcia : F. Hernández, 1998) Pawlikowski, M.; Zielinski, K.; Slowinska-Klencka, D.; Klencki, M.
To evaluate the possible antigoitrogenic effect of somatostatin, the influence of long-acting somatostatin analog - octreotide - on experimental goiter developed in rats treated with propylthiouracil was examined. Goiter formation was assessed by measurement of the main histological compartments of the thyroid as well as by morphometric analysis of the vascularization and blood supply of the gland. Although treatment with octreotide did not prevent the goiter formation, it clearly reduced blood supply and vascularization of the thyroid and counteracted propylthiouracil- induced increase in the relative volume of follicular epithelium. To conclude, the somatostatin analog - octreotide - is effective in reduction of goiter vascularisation. This finding provides a rationale for the clinical trials of the treatment of hypewascular goiter by somatostatin analogs.
Open Access
Spectral imaging for quantitative histology and cytogenetics
(Murcia : F. Hernández, 1998) Rothmann, C.; Bar-Am, I.
Evaluation of cell morphology by bright field microscopy is the pillar of histopathological diagnosis. The need for quantitative and objective parameters for diagnosis gave rise to the development of morphometric methods. Morphometry combined with spectral imaging provides multi-pixel information from a specimen, which can be used for further image processing and quantitative analysis. The spectroscopic analysis is based on the ability of a stained histological specimen to absorb, reflect, or emit photons in ways characteristic to its interactions with specific dyes. Spectral information obtained from a histological specimen is stored in a cube whose appellate signifies the two spatial dimensions of a flat sample (X and y) and the third dimension, the spectrum, representing the light intensity for every wavelength. By mathematical analysis of the cube database, it is possible to perform the function of spectralsimilarity mapping (SSM) which enables the demarcation of areas occupied by the same type of material. Spectral similarity mapping constructs new images of the specimen, revealing areas with similar stain-macromolecule characteristics and enhancing subcellular features. Spectral imaging combined with SSM reveals nuclear organization and identifies specifically the nucleoli domains. Therefore, differentiation stages as well as apoptotic and necrotic conditions are easily quantified. The commercial spectracubeTM system was developed for the application of spectral imaging in biology, recordin both transmitted light and fluorescence. The SKY^ rfi technique utilizes the advantages of the spectracubeTM for multi probe FISH and chromosome karyotyping, identifying marker chromosomes, detecting subtle chromosome translocations and clarifying complex karyotypes.
Open Access
Hepatic alterations and induction of micronuclei in rainbow trout Oncorhynchus mykiss exposed to a textile industry effluent
(Murcia : F. Hernández, 1998) Marlasca, M.J.; Sanpera, C.; Riva, M.C.; Sala, R.; Crespo, S.
Rainbow trout, Oncorhynchus mykiss, were exposed to a sublethal dose of a wool shrinkproofing effluent for 15, 30, 45 and 60 days. Liver and blood samples were taken after the exposure time together with samples of control handled fish. A light and electron microscope study was carried out to evaluate the histopathological lesions induced in the liver of treated fish. The genotoxic potential of the effluent was assessed by piscine micronucleus test. Vacuolation of liver bile preductular cells was observed in all exposed fish; abnormal lipid accumulation and basophilic foci were seen in the liver of one 30-days- and one 45-days-exposed fish, respectively. These specific alterations could be related to a pre-carcinogenic process. On the contrary, other lesions also described in all treated fish such as dilatation, vesiculation and degranulation of the rough endoplasmic reticulum, altered mitochondria, increase in myelin bodies and lysosomes and presence of phagosomes in wandering macrophages might be considered as non-specific alterations, similar to those described in fish exposed to different pollutants. Frequencies of micronucleated peripheral erythrocytes showed a significant increase following 30-days exposure.
Open Access
Modifications in the distribution of met-enkephalin in the pons of the cat, following the intravenous administration of clonidine: An immunocytochemical experimental study
(Murcia : F. Hernández, 1998) Vazquez, J.; Muñoz Madrid, Juan; García, J.C.
The distribution of rnet-enkephalin in the cat and its rnodifications following the stirnulation by intravenous clonidine, was studied with indirect irnrnunocytochernical techniques. We observed a decrease in the irnrnunoreactivity of rnet-enkephalin following the adrninistration of clonidine, relative to the controls, in the following structures: locus coeruleus, nucleus cuneforrnis, forrnatio reticularis, nucleus gigantocellularis, nucleus reticularis lateralis, nucleus reticularis, nucleus reticularis parvocellularis, nucleus sensorius superior n. trigernini, nucleus raphes, substantia grisea periventricularis, nucleus erninentiae teretis, colliculus inferior, nucleus rnotorius n. trigemini, nucleus tracto spinalis n. trigernini, tractus spinalis n. trigernini and nucleus tracto rnesencephalici n. trigernini. These experimental observations link the irnrnunoreactivity changes to the structures that are associated with the direct action of clonidine and conclude that the pars rnetencephalinergicus of the efferent pontine pathway of pain is in rnorpho-functional relationship with the analgesia produced by clonidine; an analgesic of an endogenous opiate character.
Open Access
Effects of alcohol and aging on the cingular (area 24) and frontal (area 6) cortical areas of the mouse
(Murcia : F. Hernández, 1998) Marrero-Gordillo, N.; Pérez-Delgado, M. del M.; Carmona-Calero, E.; Pérez-González, H.; Ferres Torres, R.; Castañeyra Perdomo, A.
We have studied the morphometric changes of the neurons of the cingular area 24 and frontal area 6 of the mouse, produced by age andlor chronic alcohol intake. The parameters analyzed were nuclear area of these cortical neurons and cellular density (celllneuropil coefficient). Wc dctccted a decrease in the number of neurons with age in practically al1 layers of the control animals. In the animals that chronically ingested the alcoholic solution, we also detected a decrease in the number of neurons with age, but only in layer V of the frontal cortex and in layer VI of the cingular area 24. The comparison between the control and the alcoholic group showed that alcohol intake caused an incrcasc in the nuclear area of the neurons in layer 11-111 of the frontal cortcx at 180 days, while in the cingular cortex the increase in nuclear area of its neurons was significative at 180 days in layer 11-111 and at 35 and 180 days in layers V and VI. We think that these changes are the expression of the neurona1 plasticity in both cortical areas in response to the alcohol exposure.