Publicaciones por año
Publicaciones del Departamento de Histología y Embriología
Intrinsic neurons in the mammalian ovary
Microsc Res Tech 2002 Dec 15;59(6):484-9
Hortensia D'Albora 1 , Gabriel Anesetti 1 2, Paula Lombide 1 3, W Les Dees 4, Sergio R Ojeda 5
1 Departamento de Histología y Embriología, Facultad de Medicina, CP 11800 Montevideo, Uruguay. hdalbora@fmed.edu.uy 2 Area de Histología y Embriología, Facultad de Veterinaria, CP 11600 Montevideo, Uruguay 3 Sección Biología Celular, Facultad de Ciencias, CP 11400 Montevideo, Uruguay 4 Department of Anatomy, College of Veterinary Medicine, Texas A&M University, College Station, TX 77843 5 Division of Neuroscience, Oregon Regional Primate Research Center, Oregon Health Sciences University, OR 97006
DOI: 10.1002/jemt.10231
PMID: 12467023
Pubmed: https://pubmed.ncbi.nlm.nih.gov/12467023
Texto completo: https://doi.org/10.1002/jemt.10231
Abstract:
Mammalian ovarian function is under endocrine and neural control. Although the extrinsic innervation of the ovary has been implicated in the control of both ovarian development and mature function, it is now clear that, from rats to humans, the ovary is endowed with a network of intrinsic neurons displaying diverse chemical phenotypes. This article describes the presence of these intrinsic neurons in the ovary of different mammalian species, and discusses the possible functions that they may have in the regulation of ovarian physiology.
The oestrogenized rat myometrium inhibits organotypic sympathetic reinnervation
Auton Neurosci 2002 Oct 31;101(1-2):13-22
M M Brauer a, R Chávez-Genaro a b, A Richeri a, L Viettro a, A I Frias c, G Burnstock d, T Cowen e
a Laboratorio de Biologı́a Celular, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia 3318, Montevideo 11600, Uruguay b Departamento de Histologı́a, Facultad de Medicina, Universidad de la Repūblica, Montevideo, Uruguay c Departamento de Biologı́a Animal y Humana, Facultad de Biologı́a, Universidad de La Habana, Havana, Cuba d Autonomic Neuroscience Institute, Royal Free and University College Medical School, London, UK e Department of Anatomy and Developmental Biology, University College London, Royal Free Campus, London NW3 2PF, UK
DOI: 10.1016/s1566-0702(02)00173-x
PMID: 12462355
Pubmed: https://pubmed.ncbi.nlm.nih.gov/12462355
Texto completo: https://www.autonomicneuroscience.com/article/S1566-0702(02)00173-X/abstract
Abstract:
Chronic administration of oestrogen to rats during the infantile/prepubertal period provokes, at 28 days of age, complete loss of noradrenaline-labelled intrauterine sympathetic nerves. It is not known whether oestrogen inhibits the growth or causes the degeneration of developing uterine sympathetic nerves, or whether the uterus recovers its innervation following cessation of infantile/prepubertal oestrogen treatment. In the present study, we analysed the time-course of the effects of oestrogen on the development of uterine sympathetic nerves in the rat, using histochemical methods. In addition, the pattern of sympathetic reinnervation of the uterus of intact and ovariectomised females was assessed 3 and 6 months after cessation of chronic oestrogen treatment. The ability of sympathetic nerves to reinnervate the oestrogenized uterine tissue was assessed in intraocular transplants of uterine myometrium into ovariectomised host rats. Early exposure to oestrogen did not inhibit the approach of sympathetic nerves to the uterus, but prevented the normal growth and maturation of intrauterine sympathetic fibres and abolished the innervation that reached the organ before initiation of treatment. Three or six months following cessation of oestrogen treatment, most of the sympathetic nerves were restricted to the mesometrium and mesometrial entrance, whereas intrauterine innervation remained persistently depressed as a consequence of a sustained oestrous-like state provoked by ovarian dysfunction (polycystic ovary). An organotypic regrowth of uterine sympathetic nerves was observed in ovariectomised infantile/prepubertal oestrogen-treated animals. After 5 weeks in oculo, the innervation of oestrogenized myometrial transplants was reduced by 50%, and substantial changes in the pattern of reinnervation were observed. In control transplants, 86% of the nerves were terminal varicose myometrial and perivascular nerve fibres, whereas 14% were preterminal nerve bundles. In oestrogenized myometrial transplants, 83% of the noradrenaline-labelled intercepting nerves were enlarged preterminal bundles and only 17% were terminal fibres. These results indicate that the oestrogenized myometrium is unattractive for sympathetic nerves and inhibits organotypic sympathetic reinnervation.
Peroxynitrite-induced cytotoxicity in cultured astrocytes is associated with morphological changes and increased nitrotyrosine immunoreactivity
Neurotox Res 2002 Mar;4(2):87-93
Mariana Pehar 1 2, Laura Martínez-Palma 2, Hugo Peluffo 2, Andrés Kamaid 2, Patricia Cassina 2, Luis Barbeito 1
1 Neurobiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay 2 Departamento Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
DOI: 10.1080/10298420290015818
PMID: 12829407
Pubmed: https://pubmed.ncbi.nlm.nih.gov/12829407
Texto completo: https://link.springer.com/article/10.1080/10298420290015818
Abstract:
We have established a cell culture model of spinal cord astrocytes to study the cytotoxicity of peroxynitrite. Nitric oxide (NO) has been implicated as a key contributor to neurotoxicity. NO reacts with superoxide to generate peroxynitrite, a strong oxidant and nitrating agent with deleterious cytotoxic and pro-apoptotic effects. Peroxynitrite and nitrotyrosine are formed in damaged motor neurons in amyotrophic lateral sclerosis (ALS), which are surrounded by reactive astrocytes. To determine the effects of extracellular addition of peroxynitrite, purified astrocyte monolayers prepared from neonatal rat spinal cords were exposed to peroxynitrite (0.25-0.75 mM) for 5 min and further incubated in culture medium for 24-72h. Peroxynitrite exposure did not result in apparent cell loss or damage of the monolayer. However, a substantial number of cells adopted reactive features, with long processes displaying intense immunoreactivity to glial fibrillary acidic protein (GFAP). Western blot analysis performed 24h after peroxynitrite treatment showed that GFAP levels were not modified by the oxidant. There were no changes in cell viability parameters in astrocyte cultures after peroxyintrite, indicating that astrocytes are more resistant to the oxidant than other cell types. Peroxynitrite reacts with protein-bound tyrosine residues to form nitrotyrosine. We observed a modest to strong nitrotyrosine immunoreactivity in astrocytes 24h following peroxynitrite exposure. There was a remarkable association between nitrotyrosine and high-intensity GFAP immunoreactivity in astrocytes bearing long processes. These results suggest that peroxynitrite induces a characteristic long-lasting reactive astrocytic phenotype and provide new insight into understanding the origin of reactive astrocytes occurring in ALS.
Peroxynitrite triggers a phenotypic transformation in spinal cord astrocytes that induces motor neuron apoptosis
J Neurosci Res 2002 Jan 1;67(1):21-9
Patricia Cassina 1 , Hugo Peluffo 1, Mariana Pehar 1 2, Laura Martinez-Palma 1 3, Andrés Ressia 1, Joseph S Beckman 4, Alvaro G Estévez 5, Luis Barbeito 2
1 Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay. 2 Departamento de Neurobiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Montevideo, Uruguay 3 Facultad de Veterinaria, Universidad de la República, Montevideo, Uruguay 4 Linus Pauling Institute, Department of Biochemistry and Biophysics, Oregon State University,Corvallis, Oregon 5 Department of Physiology and Biophysics, University of Alabama at Birmingham, Birmingham, Alabama
DOI: 10.1002/jnr.10107
PMID: 11754077
Pubmed: https://pubmed.ncbi.nlm.nih.gov/11754077
Texto completo: https://doi.org/10.1002/jnr.10107
Abstract:
Oxidative stress mediated by nitric oxide (NO) and its toxic metabolite peroxynitrite has previously been associated with motor neuron degeneration in amyotrophic lateral sclerosis (ALS). Degenerating spinal motor neurons in familial and sporadic ALS are typically surrounded by reactive astrocytes expressing the inducible form of NO synthase (iNOS), suggesting that astroglia may have a pathogenic role in ALS. We report here that a brief exposure of spinal cord astrocyte monolayers to peroxynitrite (0.25-1 mM) provoked long-lasting reactive morphological changes characterized by process-bearing cells displaying intense glial fibrillary acidic protein and iNOS immunoreactivity. Furthermore, peroxynitrite caused astrocytes to promote apoptosis of embryonic motor neurons subsequently plated on the monolayers. Neuronal death occurred within 24 hr after plating, as evidenced by the presence of degenerating motor neurons positively stained for activated caspase-3 and nitrotyrosine. Motor neuron death was largely prevented by NOS inhibitors and peroxynitrite scavengers but not by trophic factors that otherwise will support motor neuron survival in the absence of astrocytes. The bacterial lipopolysaccharide, a well-known inflammatory stimulus that induces iNOS expression in astrocytes, provoked the same effects on astrocytes as peroxynitrite. Thus, spinal cord astrocytes respond to extracellular peroxynitrite by adopting a phenotype that is cytotoxic to motor neurons through peroxynitrite-dependent mechanisms.
Neural retina of chick embryo in organ culture: effects of blockade of growth factors by suramin
Cell Tissue Res 2001 Jun;304(3):323-31
A Cirillo 1 , S Chifflet 2 , B Villar 1
1 Departmento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay. acirillo@fmed.edu.uy 2 Departamento de Bioquímica. Facultad de Medicina, Universidad de la República, Montevideo, Uruguay
DOI: 10.1007/s004410100355
PMID: 11456408
Pubmed: https://pubmed.ncbi.nlm.nih.gov/11456408
Texto completo: https://dx.doi.org/10.1007/s004410100355
Abstract:
The neural retina is a highly organized organ whose final histoarchitecture depends on the presence of diverse growth factors and on their interactions with extracellular matrix components. However, the role of growth factors on retinal development is not fully understood. Suramin has been shown to produce diverse cellular effects via the simultaneous block of the action of several growth factors. We have therefore studied the effects of suramin on organotypic culture of chick embryo neural retina in order to gain further insights into the participation of growth factors in neural retinal development. Neural retina was incubated for 24 h with suramin at 50-200 microM and then processed to determine cell proliferation, nuclear morphology, and actin distribution. Suramin provoked extensive morphological changes revealed by a decrease in BrdU incorporation, alterations in cellular organization, and disruption of the outer limiting membrane, with the emergence of cellular elements through it. All of these effects were dose-dependent and markedly attenuated by the simultaneous presence of suramin and fibroblast growth factor 2 (FGF-2) in the culture medium. These findings indicate that suramin induces pleiotropic effects on the histoarchitecture of the chicken neural retina in organ culture and suggest that FGF-2 is one of the biological modulators involved in the maintenance of the structural organization of the chicken neural retina.
Adaptative responses of spinal astrocytes to oxidative stress
Prog Brain Res 2001 2001:132:413-25
P Cassina 2, H Peluffo 1 2, L Barbeito 1
1 División de Neurobiología Celular y Molecular, Instituto de Investigaciones Biológicas Clemente Estable, Avenida Italia 3318, 11600 Montevideo, Uruguay 2 Departamento de Histología y Embriología, Facultad de Medicina, Montevideo, Uruguay
DOI: 10.1016/S0079-6123(01)32092-7
PMID: 11545008
Pubmed: https://pubmed.ncbi.nlm.nih.gov/11545008
Texto completo: https://www.sciencedirect.com/science/article/abs/pii/S0079612301320927?via%3Dihub
Abstract:
Effects of chronic oestrogen treatment are not selective for uterine noradrenaline-containing sympathetic nerves: a transplantation study
J Anat 2000 Apr;196 ( Pt 3):347-55
M M Brauer 1 , R Chávez-Genaro 2, J Llodrá 1, A Richeri 1, M C Scorza 1
1 División Biología Celular, Instituto de Investigaciones Biológicas Clemente Estable 2 Departamento de Histología y Embriología, Facultad de Medicina, Montevideo, Uruguay
DOI: 10.1046/j.1469-7580.2000.19630347.x
PMID: 10853957
Pubmed: https://pubmed.ncbi.nlm.nih.gov/10853957
Texto completo: https://onlinelibrary.wiley.com/doi/10.1046/j.1469-7580.2000.19630347.x
Abstract:
Previous studies have shown that chronic administration of oestrogen during postnatal rat development dramatically reduces the total content of noradrenaline in the uterine horn, abolishes myometrial noradrenergic innervation and reduces noradrenaline-fluorescence intensity of intrauterine perivascular nerve fibres. In the present study we analysed if this response is due to a direct and selective effect of oestrogen on the uterine noradrenaline-containing sympathetic nerves, using the in oculo transplantation method. Small pieces of myometrium from prepubertal rats were transplanted into the anterior eye chamber of adult ovariectomised host rats. The effect of systemic chronic oestrogen treatment on the reinnervation of the transplants by noradrenaline-containing sympathetic fibres from the superior cervical ganglion was analysed on cryostat tissue sections processed by the glyoxylic acid technique. In addition, the innervation of the host iris was assessed histochemically and biochemically. The histology of the transplants and irises was examined in toluidine blue-stained semithin sections. These studies showed that after 5 wk in oculo, the overall size of the oestrogen-treated transplants was substantially larger than controls, and histology showed that this change was related to an increase in the size and number of smooth muscle cells within the transplant. Chronic oestrogen treatment did not provoke trophic changes in the irideal muscle. Histochemistry showed that control transplants had a rich noradrenergic innervation, associated with both myometrium and blood vessels. Conversely, in oestrogen-treated transplants only occasional fibres were recognised, showing a reduced NA fluorescence intensity. No changes in the pattern and density of innervation or in the total content of noradrenaline of the host irises were detected after chronic exposure to oestrogen. We interpreted these results to indicate that the effects of oestrogen on uterine noradrenaline-containing sympathetic nerves are neither selective or direct, but result from an interaction between sympathetic nerve fibres with the oestradiol-primed uterine tissue. A potential effect of oestrogen on the neurotrophic capacity of the uterus is discussed.
Intrinsic neurons in the rat ovary: an immunohistochemical study
Cell Tissue Res 2000 Apr;300(1):47-56
H D'Albora 1 , P Lombide 1, S R Ojeda 2
1 Laboratory of Biology of Reproduction, Department of Histology and Embryology, School of Medicine, Universidad de la República, Gral. Flores 2125, CP 11800, Montevideo, Uruguay 2 Division of Neuroscience, Oregon Regional Primate Research Center, Beaverton, OR, USA
DOI: 10.1007/s004419900130
PMID: 10805074
Pubmed: https://pubmed.ncbi.nlm.nih.gov/10805074
Texto completo: https://link.springer.com/article/10.1007/s004419900130
Abstract:
Previous studies have shown the presence of neuronal perikarya in the primate ovary, but not in the ovary from Sprague-Dawley rats. We report here that while such intrinsic neurons are indeed absent in this strain of rats, they can be visualized in the ovary from Wistar rats. The neurons, identified by their morphology and by the expression of NeuN (a neuron-specific nuclear protein), were detected at all postnatal intervals examined, from 14 h after birth to 50 days of age. While they were present in the ovarian hilum and medulla at all ages studied, neurons first appeared in the ovarian cortex during the juvenile period (postnatal days 10-20). In all cases, the size of the neuronal soma increased significantly during prepubertal development, reaching maximal values before puberty. Some neurons were catecholaminergic, as indicated by their content of immunoreactive tyrosine hydroxylase (TH), the rate-limiting enzyme of catecholamine biosynthesis. Some showed neuropeptide Y (NPY) immunoreactivity. TH-positive neurons were seen either in isolation or clustered in ganglion-like structures in both the ovarian cortex and medulla. These results indicate that ovarian neurons are not present in all strains of rats, but when present, the chemical phenotype of some of them is of a sympathetic nature, similar to that described in primates.
Transient expression of nitric oxide synthase in the hypoglossal nucleus of the rat during early postnatal development
Neurosci Lett 1999 Nov 5;275(1):5-8
C Vazquez 1 2, G Anesetti 1 3, L Martinez Palma 1 3
1 Laboratory of Developmental Neurobiology, Department of Histology and Embryology, Faculty of Medicine, Avda. Gral Flores 2125, CP 11800, Montevideo, Uruguay 2 Institute of Neurology, Clinical Hospital, Montevideo, Uruguay 3 Histology and Embryology Area, Department of Morphology and Development, Faculty of Veterinary Sciences, Montevideo, Uruguay
DOI: 10.1016/s0304-3940(99)00686-2
PMID: 10554971
Pubmed: https://pubmed.ncbi.nlm.nih.gov/10554971
Texto completo: https://linkinghub.elsevier.com/retrieve/pii/S0304-3940(99)00686-2
Abstract:
The present study investigates the presence of nitric oxide synthase (NOS) by the nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemical reaction and immunohistochemistry with neuronal NOS (nNOS) antibody during postnatal development of hypoglossal nucleus (XII) in the rat. Our results showed that the enzyme expression was limited to a subset of cells in the dorsal division of the nucleus. Retrogradely labeling with diamidino yellow (DY) from the tongue indicates that these cells were motoneurons. NOS expression was transient, being detectable during the first 3 postnatal weeks, suggesting a role for nitric oxide in the development and maturation of this subset of cranial motoneurons.
Characterization of MARCKS (Myristoylated alanine-rich C kinase substrate) identified by a monoclonal antibody generated against chick embryo neural retina
Biochem Biophys Res Commun 1999 257(2):480-7
F R Zolessi 1 3 , U Hellman 4 , A Baz 2 , C Arruti 1
1 Laboratorio de Cultivo de Tejidos, Sección Biología Celular, Universidad de la República, Montevideo, Uruguay 2 Cátedra de Inmunología, U.A., Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay 3 Departamento de Histología y Embriología, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay 4 Ludwig Institute for Cancer Research, Uppsala, Sweden
DOI: 10.1006/bbrc.1999.0490
PMID: 10198238
Pubmed: https://pubmed.ncbi.nlm.nih.gov/10198238
Texto completo: https://www.sciencedirect.com/science/article/abs/pii/S0006291X99904904?via%3Dihub
Abstract:
To identify molecular markers of cell differentiation in developing nervous tissue, monoclonal antibodies against chick embryo neural retina were made. One of them, 3C3mAb, recognized a developmentally regulated antigen present in several organs of the CNS. Data from MALDI-TOF mass spectrometry and peptide sequencing of the immuno-affinity purified protein indicated identity of the antigen with MARCKS. The immunoreactive material was always found as a unique polypeptide (Mr 71 kDa) in SDS-PAGE, however isoelectrofocusing revealed the existence of several bands (pI ranging from 4.0 to 4.5). Interestingly some retinal cell types, as photoreceptors, exhibited an extremely significant decrease in the intensity of the immunoreactive material during the final phases of terminal differentiation while others, as some retinal neurons, maintained the immunoreactivity when fully differentiated. Taken together these results indicate that MARCKS, a protein susceptible of several posttranslational modifications as myristoylation and phosphorylation at variable extent, may act differently in neural retina cell types.