RESUMEN
In the present study, we investigated the involvement of sulfated glycosaminoglycans in both the in vivo development and adhesion of T. cruzi epimastigotes to the luminal surface of the digestive tract of the insect vector, Rhodnius prolixus. Pre-incubation of T. cruzi, Dm 28c epimastigotes with heparin, chondroitin 4-sulfate, chondroitin 6-sulfate or protamine chloridrate inhibited in vitro attachment of parasites to the insect midgut. Enzymatic removal of heparan sulfate moieties by heparinase I or of chondroitin sulfate moieties by chondroitinase AC from the insect posterior midgut abolished epimastigote attachment in vitro. These treatments also reduced the labelling of anionic sites exposed at the luminal surface of the perimicrovillar membranes in the triatomine midgut epithelial cells. Inclusion of chondroitin 4-sulfate or chondroitin 6-sulfate and to a lesser extent, heparin, in the T. cruzi-infected bloodmeal inhibited the establishment of parasites in R. prolixus. These observations indicate that sulfated glycosaminoglycans are one of the determinants for both adhesion of the T. cruzi epimastigotes to the posterior midgut epithelial cells of the triatomine and the parasite infection in the insect vector, R. prolixus.
Asunto(s)
Enfermedad de Chagas/parasitología , Tracto Gastrointestinal/parasitología , Glicosaminoglicanos/farmacología , Insectos Vectores/parasitología , Rhodnius/parasitología , Trypanosoma cruzi/efectos de los fármacos , Animales , Adhesión Celular/efectos de los fármacos , Células Epiteliales/parasitología , Insectos Vectores/citología , Larva , Masculino , Rhodnius/citología , Trypanosoma cruzi/crecimiento & desarrolloRESUMEN
The aim of this study was to characterize the compartmental distribution of sulfated glycosaminoglycans (S-GAGs) in adults and their occurrence during the development of the earthworm Eisenia andrei. S-GAGs were extracted from the body of earthworms to identify their composition and the time of their appearance and disappearance in embryonic, newborn, juvenile, and adult earthworms. S-GAGs were also analyzed in earthworm tissue using histochemical metachromatic staining. Purified S-GAGs obtained from the whole body of adult earthworms were composed of chondroitin sulfate (CS) and heparan sulfate (HS). In addition, an unknown, highly sulfated polysaccharide (HSP) was detected. In order to characterize specifically the S-GAG composition in the integument, earthworms were dissected and as much as possible of their viscera was removed. HS and CS were the predominant sulfated polysaccharides in the dissected integument, whereas in viscera, CS, HS and the HSP were found in proportions similar to those identified in the body. The qualitative S-GAG composition in juveniles was similar to that obtained from adult earthworms. CS was the predominant S-GAG in newborn earthworms, accompanied by lesser amounts of HS and by tiny amounts of the HSP. This study provides a detailed descriptive account of the pattern of S-GAG synthesis during development, and also the characterization of the tissue distribution of these compounds in the body of earthworms.
Asunto(s)
Sulfatos de Condroitina/análisis , Heparitina Sulfato/análisis , Oligoquetos/química , Animales , Sulfatos de Condroitina/química , Heparitina Sulfato/química , Histocitoquímica , Oligoquetos/embriología , Oligoquetos/crecimiento & desarrollo , Distribución TisularRESUMEN
The composition of sulfated glycosaminoglycans (GAGs) and the tissue distribution of chondroitin sulfate (CS) were analyzed in deeply infiltrating endometriosis (DIE) of rectosigmoid, using metachromatic staining, and biochemical analysis employing electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against CS. The sulfated GAGs were characterized as dermatan sulfate (DS), heparan sulfate (HS) and CS; and DS strongly predominated compared to HS and CS. Immunostaining procedures showed that CS was concentrated in the endometriosis foci, distributed throughout the stroma around the glands. This is the first report describing the composition of sulfated GAGs and the tissue location of CS in DIE by means of histochemical, biochemical and immunohistochemical analyses. These results confirmed that in DIE of rectosigmoid, as in eutopic endometrium [Nasciutti, L.E., Ferrari, R., Berardo, P.T., Souza, M.L.S., Takiya, C.M., Borojevic, R., Abrao, M.S., Silva, L.C.F., 2006. Distribution of chondroitin sulfate in human endometrium. Micron 37, 544-550], CS was the dominant sulfated GAG in stroma of the lesion foci.
Asunto(s)
Sulfatos de Condroitina/análisis , Endometriosis/patología , Glicosaminoglicanos/química , Adulto , Dermatán Sulfato/análisis , Femenino , Heparitina Sulfato/análisis , Histocitoquímica , Humanos , Inmunohistoquímica , Persona de Mediana EdadRESUMEN
We determined the disaccharide composition of dermatan sulfate (DS) purified from the skin of the electric eel Electrophorus electricus. DS obtained from the electric eel was composed of non-sulfated, mono-sulfated disaccharides bearing esterified sulfate groups at positions C-4 or C-6 of N-acetyl galactosamine (GalNAc), and disulfated disaccharides bearing esterified sulfate groups at positions C-2 of the uronic acid and at position C-4 or C-6 of GalNAc. The anticoagulant, antithrombotic and bleeding effects of electric eel skin DS were compared to those of porcine DS and also to those described previously for DS purified from skin of eel, Anguilla japonica. DS from electric eel is a potent anticoagulant due to a high heparin co-factor II (HC II) activity. The electric eel DS has a higher potency to prevent thrombus formation on an experimental model and a lower bleeding effect in rats than the porcine DS. Interestingly, it was recently demonstrated that DS obtained from skin of the eel Anguilla japonica, which possesses a disaccharide composition very similar to that of electric eel skin DS described here, did not show anticoagulant activity. Thus, the anticoagulant activity of electric eel skin DS is not merely a consequence of its charge density. We speculate that the differences among the anticoagulant activities of these three DS may be related to different arrangements of the disulfated disaccharide domain for binding to HC II within their polysaccharide chains and that it may be more efficiently arranged along the carbohydrate chain in electric eel skin DS than in the two other types of DS.
Asunto(s)
Anticoagulantes/química , Anticoagulantes/farmacología , Dermatán Sulfato/química , Dermatán Sulfato/farmacología , Electrophorus , Piel/química , Animales , Anticoagulantes/aislamiento & purificación , Coagulación Sanguínea/efectos de los fármacos , Dermatán Sulfato/aislamiento & purificación , Humanos , Ratas , PorcinosRESUMEN
The electrogenic tissue of the electric eel Electrophorus electricus (L.) is distributed in three well-defined electric organs, the Main electric organ, Sach's organ and Hunter's organ. Sulfated glycosaminoglycan (GAG) composition was characterized in the three electric organs of the electric eel. Sulfated GAGs were analyzed in the electric organs using metachromatic staining, biochemical analysis including electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against chondroitin sulfate (CS). Our results showed in the three electric organs that CS was the main sulfated GAG species detected, accompanied by small and diminutive amounts of CS/dermatan sulfate hybrid chains and heparan sulfate (HS), respectively. However, HS was not detected in the Sach's organ. CS was predominantly detected in the innervated membrane face of the electroplaques in the three electric organs. Our findings extend previous observations on the GAG composition in the electric organs of E. electricus and provide new information regarding the tissue distribution and location of CS.
Asunto(s)
Sulfatos de Condroitina/metabolismo , Órgano Eléctrico/metabolismo , Electrophorus/metabolismo , Animales , Dermatán Sulfato/metabolismo , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , InmunohistoquímicaRESUMEN
Sulfated glycosaminoglycan (GAG) composition was characterized in the human endometrium during proliferative and secretory phases of the menstrual cycle. Sulfated GAGs were analyzed in endometrium tissue using metachromatic staining, biochemical analysis including electrophoresis before and after specific enzymatic or chemical degradations, and immunostaining with an antibody against chondroitin sulfate (CS). Our results showed that CS was the main sulfated GAG species detected, accompanied by small amounts of heparan sulfate and dermatan sulfate. CS was distributed overall the connective stroma, around arteriole vessels and glands, and there was no important difference in the immunostaining between the proliferative and secretory endometrium phases. Our findings extend previous observations on the GAG composition in the human endometrium providing new information regarding the tissue distribution and location of endometrial CS.
Asunto(s)
Sulfatos de Condroitina/metabolismo , Endometrio/anatomía & histología , Endometrio/metabolismo , Adulto , Femenino , Glicosaminoglicanos/metabolismo , Humanos , Inmunohistoquímica , Ciclo Menstrual/metabolismo , Persona de Mediana Edad , Distribución TisularRESUMEN
Sulfated glycosaminoglycans (GAGs) were isolated and characterized in thoracic muscle, fat body, whole digestive tract (stomach+intestine) and reproductive tract of adult male cockroaches, Periplaneta americana. Heparan sulfate (HS) was the predominant sulfated GAG species in the tissues analyzed, corresponding to more than 90% of the total sulfated GAG content. In both the thoracic muscle and fat body it was the only sulfated GAG species detected. We also determined the location of sulfated GAGs in most of these organs by histochemical analysis using 1,9-dimethylmethylene blue. In the thoracic muscle, sulfated GAG metachromatic staining was detected only in the connective tissue that surrounds the muscle bundles or fascicles. In the intestinal tract, metachromatic staining was observed in both epithelial and lining columnar cells. Only spermatozoa presented metachromatic material in the male reproductive tract. Since, HS corresponds to 90-100% of total sulfated GAGs in these tissues, the metachromatic staining specifically reflects the location of this particular sulfated GAG in these organs. In conclusion, the present study extends previous observations on the GAG composition in cockroaches providing new information on the tissue distribution and location of HS in several internal organs of adult males of the cockroach P. americana.
Asunto(s)
Glicosaminoglicanos/química , Heparitina Sulfato/metabolismo , Periplaneta/química , Animales , Sistema Digestivo/química , Sistema Digestivo/metabolismo , Cuerpo Adiposo/química , Cuerpo Adiposo/metabolismo , Genitales Masculinos/química , Genitales Masculinos/metabolismo , Glicosaminoglicanos/metabolismo , Heparitina Sulfato/análisis , Heparitina Sulfato/química , Masculino , Músculos/química , Especificidad de Órganos , Especificidad de la EspecieRESUMEN
The characterization of sulfated glycosaminoglycans (GAGs) in hematophagous arthropod vectors in general has been limited, with the exception of the studies in the triatomine Rhodnius prolixus. Heparan sulfate (HS) and chondroitin sulfate (CS) were previously identified and structurally characterized in extracts of whole bodies of fourth instar larvae of R. prolixus. Recently, we showed the expression of these two sulfated GAGs in specific body tissues of adult males and females and in embryos of R. prolixus. In the present work, we identified and compared the sulfated GAG composition in specific tissues of adult insects and in embryos of another triatomine species, Triatoma brasiliensis. Sulfated GAGs were isolated from the fat body, intestinal tract, and the reproductive tracts of adult insects and from embryos. Only HS and CS were found in the tissues analyzed. The present results extend the initial observations on the sulfated GAG composition in R. prolixus by showing that these molecules are widely distributed among internal organs of triatomines. These observations may be useful for future investigations aiming to evaluate the possible implication of these compounds in physiological events that take place in a specific organ(s) in these insects.
Asunto(s)
Sulfatos de Condroitina/metabolismo , Heparitina Sulfato/metabolismo , Insectos Vectores/metabolismo , Rhodnius/metabolismo , Triatoma/metabolismo , Animales , Enfermedad de Chagas , Cuerpo Adiposo/metabolismo , Femenino , Gónadas/metabolismo , Larva/metabolismo , Masculino , Especificidad de ÓrganosRESUMEN
We compared the disaccharide composition of dermatan sulfate (DS) purified from the ventral skin of three species of rays from the Brazilian seacoast, Dasyatis americana, Dasyatis gutatta, Aetobatus narinari and of Potamotrygon motoro, a fresh water species that habits the Amazon River. DS obtained from the four species were composed of non-sulfated, mono-sulfated disaccharides bearing esterified sulfate groups at positions C-4 or C-6 of N-acetyl galactosamine (GalNAc), and disulfated disaccharides bearing esterified sulfate groups at positions C-2 of the uronic acid and at position C-4 or C-6 of GalNAc. However, DS from the skin of P. motoro presented a very low content of the disulfated disaccharides. The anticoagulant actions of ray skin DS, measured by both APTT clotting and HCII-mediated inhibition of thrombin assays, were compared to that of mammalian DS. DS from D. americana had both high APTT and HCII activities, whereas DS from D. gutatta showed activity profiles similar to those of mammalian DS. In contrast, DS from both A. narinari and P. motoro had no measurable activity in the APTT assay. Thus, the anticoagulant activity of ray skin DS is not merely a consequence of their charge density. We speculate that the differences among the anticoagulant activities of these three DS may be related to both different composition and arrangements of the disulfated disaccharide units within their polysaccharide chains.
Asunto(s)
Anticoagulantes/química , Coagulación Sanguínea/efectos de los fármacos , Dermatán Sulfato/química , Rajidae , Animales , Anticoagulantes/aislamiento & purificación , Anticoagulantes/farmacología , Dermatán Sulfato/aislamiento & purificación , Dermatán Sulfato/farmacología , Estructura Molecular , Especificidad de la EspecieRESUMEN
Acharan sulfate, a recently discovered glycosaminoglycan isolated from Achatina fulica, has a major disaccharide repeating unit of -->4)-2-acetyl,2-deoxy-alpha-d-glucopyranose(1-->4)-2-sulfo-alpha-l-idopyranosyluronic acid (1-->, making it structurally related to both heparin and heparan sulfate. It has been suggested that this glycosaminoglycan is polydisperse, with an average molecular mass of 29 kDa and known minor disaccharide sequence variants containing unsulfated iduronic acid. Acharan sulfate was found to be located in the body of this species using alcian blue staining and it was suggested to be the main constituent of the mucus. In the present work, we provide further information on the structure and compartmental distribution of acharan sulfate in the snail body. Different populations of acharan sulfate presenting charge and/or molecular mass heterogeneities were isolated from the whole body, as well as from mucus and from the organic shell matrix. A minor glycosaminoglycan fraction susceptible to degradation by nitrous acid was also purified from the snail body, suggesting the presence of N-sulfated glycosaminoglycan molecules. In addition, we demonstrate the in vivo metabolic labeling of acharan sulfate in the snail body after a meal supplemented with [35S]free sulfate. This simple approach might be applied to the study of acharan sulfate biosynthesis. Finally, we developed histochemical assays to localize acharan sulfate in the snail body by metachromatic staining and by histoautoradiography following metabolic radiolabeling with [35S]sulfate. Our results show that acharan sulfate is widely distributed among several organs.
Asunto(s)
Glicosaminoglicanos/química , Glicosaminoglicanos/metabolismo , Caracoles/química , Animales , Glicosaminoglicanos/aislamiento & purificación , Peso Molecular , Moco/química , Moco/metabolismo , Resonancia Magnética Nuclear Biomolecular , Caracoles/anatomía & histología , Caracoles/metabolismo , Radioisótopos de Azufre , Distribución TisularRESUMEN
We have previously characterized heparan sulfate (HS) as the major ovarian sulfated glycosaminoglycan (GAG) in females of Rhodnius prolixus, while chondroitin sulfate (CS) was the minor component. Using histochemical procedures we found that GAGs were concentrated in the ovarian tissue but not found inside the oocytes. Here, we extend our initial observations of GAG expression in R. prolixus by characterizing these molecules in other organs: the fat body, intestinal tract, and the reproductive tracts. Only HS and CS were found in the three organs analyzed, however CS was the major GAG species in these tissues. We also determined the compartmental distribution of GAGs in these organs by histochemical analysis using 1,9-dimethylmethylene blue, and evaluated the specific distribution of CS within both male and female reproductive tracts by immunohistochemistry using an anti-CS antibody. We also determined the GAG composition in eggs at days 0 and 6 of embryonic development. Only HS and CS were found in eggs at day 6, while no sulfated GAGs were detected at day 0. Our results demonstrate that HS and CS are the only sulfated GAG species expressed in the fat body and in the intestinal and reproductive tracts of Rhodnius male and female adults. Both sulfated GAGs were also identified in Rhodnius embryos. Altogether, these results show no qualitative differences in the sulfated GAG composition regarding tissue-specific or development-specific distribution.
Asunto(s)
Glicosaminoglicanos/metabolismo , Rhodnius/metabolismo , Animales , Sulfatos de Condroitina/metabolismo , Cuerpo Adiposo/metabolismo , Femenino , Heparitina Sulfato/metabolismo , Inmunohistoquímica , Masculino , Oogénesis , Rhodnius/crecimiento & desarrollo , Distribución TisularAsunto(s)
Glicosaminoglicanos/metabolismo , Heparitina Sulfato/metabolismo , Ixodidae/fisiología , Animales , Huevos , Electroforesis en Gel de Agar , Femenino , Glicosaminoglicanos/análisis , Proteoglicanos de Heparán Sulfato/metabolismo , Heparitina Sulfato/análisis , Mucosa Intestinal/metabolismo , Intestinos/química , Ixodidae/crecimiento & desarrollo , Ixodidae/metabolismo , Ovario/química , Ovario/metabolismoRESUMEN
Glycosaminoglycans are thought to accumulate in formative lesions like drug-induced gingival overgrowth. Recent evidences, however, suggest that the amounts of glycosaminoglycans are comparable in overgrown and healthy gingiva. Besides, alterations in the size distribution of glycosaminoglycan molecules isolated from phenytoin-induced overgrown samples have also been suggested. Therefore, we sought to determine possible differences in molecular size distribution of gingival glycosaminoglycans in other types of drug-induced overgrowths. Purified gingival glycosaminoglycans from healthy and cyclosporin- and nifedipine-induced overgrown gingival tissues were analyzed by agarose gel electrophoresis and their molecular-size distribution was evaluated by both gel filtration chromatography and polyacrylamide gel electrophoresis. Our results on the gingival glycosaminoglycan composition showed presence of chondroitin sulfate, dermatan sulfate, heparan sulfate and hyaluronic acid in all types of gingival tissues examined. In addition, hyaluronic acid was predominantly of a large size eluting near to the void volume of a Superose-6 column, while the sulfated glycosaminoglycans were mainly composed of low molecular size glycosaminoglycans. Our results show no differences in the molecular-size distribution of hyaluronic acid and sulfated glycosaminoglycans among healthy and drug-induced overgrown gingival tissues.
Asunto(s)
Bloqueadores de los Canales de Calcio/efectos adversos , Ciclosporina/efectos adversos , Encía/química , Sobrecrecimiento Gingival/metabolismo , Glicosaminoglicanos/química , Inmunosupresores/efectos adversos , Nifedipino/efectos adversos , Adolescente , Adulto , Sulfatos de Condroitina/aislamiento & purificación , Cromatografía en Gel , Dermatán Sulfato/aislamiento & purificación , Electroforesis en Gel de Agar , Electroforesis en Gel de Poliacrilamida , Glicosaminoglicanos/aislamiento & purificación , Heparitina Sulfato/aislamiento & purificación , Humanos , Ácido Hialurónico/aislamiento & purificación , Persona de Mediana Edad , Estructura Molecular , Peso Molecular , SefarosaRESUMEN
OBJECTIVES: Several investigators have reported an increase in urinary glycosaminoglycans (GAGs) in patients with relapsing polychondritis (RP). The aim of this investigation is to analyze the composition and structure of urinary GAGs from a Brazilian patient with RP. DESIGN AND METHODS: The identification and structural analyses of the GAGs were made by electrophoresis and degradation with specific enzymes and identification of their disaccharides products by HPLC chromatography. RESULTS: The disaccharide products formed from RP urinary chondroitin sulfate (CS) by action of chondroitin ABC lyase showed a substantial relative increase of nonsulfated disaccharides with a relative decrease of 6-sulfated disaccharides compared to control subjects. In addition, a significant change of the ratio of CS and heparan sulfate was also observed in the RP patient. CONCLUSION: The RP patient analyzed has shown a structural anomaly of the urinary CS and this may contribute to the diagnosis of this disease.
Asunto(s)
Glicosaminoglicanos/química , Glicosaminoglicanos/orina , Policondritis Recurrente/orina , Adulto , Cromatografía Líquida de Alta Presión , Humanos , Masculino , Valores de ReferenciaRESUMEN
Heparan sulfate (HS) present on the surface of hemopoietic stromal cells has important roles in the control of adhesion and growth of hemopoietic stem and progenitor cells. Recent studies have characterized several different heparan sulfate proteoglycans (HSPGs) from both human and murine bone marrow stromal cells. In the present study, we have compared the molecular structure of HS, metabolically labeled with [(35)S]-sulfate produced by two distinct preparations of murine hemopoietic stromal cell lines. These comprised a bone marrow-derived cell line S17 and a fetal liver-derived cell line AFT024. [(35)S]-HS was examined in the cell layers and in the culture medium. We identified and measured the relative proportions of the various glycosaminoglycans (GAGs) in the two stromal cell lines. Chondroitin sulfate (CS) was preponderantly secreted by the stromal cell lines, while HS was relatively more abundant in the cell-associated fractions. The two types of stromal cells differ in their HS composition, mainly due to different patterns of N- and O-sulfation. The two stromal cell lines expressed mRNA for different HSPGs. Data from reverse transcription PCR revealed that the two stromal cell lines expressed mRNA for glypican and syndecan4. Only AFT024 cell line expressed mRNA for betaglycan. There was no evidence for expression of mRNA for both syndecan1 and syndecan2. [(35)S]-sulfated macromolecules could be released from the cell surface of both stromal cell lines by phosphatidylinositol phospholipase C (PI-PLC), which is consistent with the expression of glypican detected by PCR experiments.
Asunto(s)
Células de la Médula Ósea/metabolismo , Células Madre Hematopoyéticas/metabolismo , Heparitina Sulfato/metabolismo , Hígado/metabolismo , Animales , Línea Celular Transformada , Membrana Celular/metabolismo , Condroitín Liasas/química , Condroitín Liasas/metabolismo , Cromatografía por Intercambio Iónico/métodos , Citocinas/biosíntesis , Cartilla de ADN , Disacáridos/biosíntesis , Disacáridos/química , Electroforesis en Gel de Agar , Sangre Fetal/citología , Sangre Fetal/metabolismo , Hematopoyesis , Células Madre Hematopoyéticas/citología , Heparina/química , Heparina/metabolismo , Heparitina Sulfato/análisis , Humanos , Hígado/citología , Ratones , Ácido Nitroso/química , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células del Estroma/metabolismo , Radioisótopos de Azufre , Factores de TiempoRESUMEN
Although some studies have shown a possible modulation of the stroma on the hormonal secretion, it is not clear as to what are the requirements for these cellular interactions. In the present work, a homogeneous and continuous lineage of rat adenohypophysis stromal cells (APS9 cells) obtained from rat adenohypophysis primary culture was established. Using immunocytochemical methods and electron microscopy, we have characterised APS9 cells as elongated fibroblastoid-like cells with intercellular contacts, expressing alpha-smooth muscle actin, type IV collagen and laminin. By biochemical procedures, higher amounts of chondroitin sulphate and heparan sulphate were found in the pericellular and extracellular compartments of APS9 cell culture. In order to evaluate the possible effects of APS9 cell on GH(3)B(6) prolactin-secreting cell survival and/or proliferation, we established co-culture and proliferation assays. When GH(3)B(6) cells were cultivated on APS9 cell substrate, they displayed an organisation of many cellular cords strongly attached and covering all the stromal cell area, establishing punctual interactions or extensive surface associations between adjacent cells. Prolactin immunoreactivity appeared to be more scattered throughout the cytoplasm and accumulated in its periphery. When plated on glass coverslips, on newborn rat skin fibroblasts, on murine haematopoietic bone marrow stroma cell line or on murine foetal liver stroma cell line, GH(3)B(6) cells changed their organisation and presented a decrease in cell number and adherence to the substrate. Our results showed that the APS9 cell/GH(3)B(6) cell interactions favour cell growth and probably PRL secretion, and raises questions about the specificity of different organs and/or animal species stromas on the hormone secretion.
Asunto(s)
Comunicación Celular/fisiología , Adenohipófisis/citología , Prolactina/metabolismo , Células del Estroma/citología , Animales , División Celular , Línea Celular , Linaje de la Célula , Tamaño de la Célula , Técnicas de Cocultivo , Masculino , Ratones , Microscopía Fluorescente , Adenohipófisis/fisiología , Ratas , Ratas Wistar , Células del Estroma/fisiologíaRESUMEN
In the developing mammalian midbrain, radial glial cells are divided into median formations and lateral radial systems with differential properties including rate and timing of cell proliferation, expression of cytoskeletal and calcium-binding proteins, storage of glycogen and relations to afferent fiber systems. To test hypothesis that radial glial cells of median and lateral midbrain sectors and/or their derivatives are heterogeneous in their relations with local neurons, an in vitro system has been developed and has also been characterized in terms of extracellular matrix (ECM) components. Confluent astrocyte cultures, derived from median (M) or lateral (L) embryonic mouse midbrain sectors, were used as substrates for culturing dissociated cells from median (m) or lateral (l) sectors of embryonic midbrains. In spite of the morphological invariance of glial substrates at confluency, cells that were plated onto these substrates and that were immunoreactive for neuronal markers (MAP2, polysialylated N-CAM or betaIII tubulin) showed differences in the aggregation of somata and in the length, caliber and branching of neurites. These differences, which depend mostly on the sector of origin of astrocytes (L: permissive, M: non-permissive for neuronal growth), suggest that the substrates may differ in adhesiveness and/or their carrying of growth-promoting vs. growth-interfering molecules. Indeed, L and M cultures differ in laminin deposition patterns (L: fibrillar, M: punctate pattern). Furthermore, sulfated glycosaminoglycans (s-GAGs) isolated from the pericellular (P), intracellular (I) and extracellular (E) compartments of these sectoral cultures also showed correlations with the ability to support neurite growth. The total amount of s-GAGs in M cultures was twice that in L cultures and was particularly high in the P compartment, with about 3 times as much heparan sulfate (HS) and about 15 times as much chondroitin sulfate (CS) in this fraction of M than in the corresponding compartment of L glia. Our results indicate that cultured astrocytes have heterogeneous properties including different organizatio of their extracellular matrix that reflect the roles played by their parent radial glia in regions favorable to axonal growth or barrier regions of the developing brain.