M. de León
University of Salamanca
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Brain Research Bulletin | 1990
Rafael Coveñas; J.A. Aguirre; M. de León; J.R. Alonso; J.A. Narváez; R. Arévalo; S. González-Barón
By using intratissue injections of colchicine and an indirect immunoperoxidase technique, we studied the distribution of cell bodies and fibers containing neuropeptide Y-like immunoreactivity in the brain stem of the cat. The densest clusters of immunoreactive perikarya were observed in the following nuclei: anteroventral cochlear, lateral reticular (internal and external divisions), dorsal tegmental, inferior colliculus and dorsal nucleus of the lateral lemniscus. By contrast, the nuclei abducens, the nucleus of the trapezoid body, preolivary, interpeduncularis, infratrigeminal, gigantocellular tegmental field, coeruleus and dorsal motor nucleus of the vagus had the lowest density. Finally, a moderate density of neuropeptide Y-like immunoreactive cell bodies was found in the nuclei: lateral tegmental field, laminar spinal trigeminal, praepositus hypoglossi, superior colliculus, lateral vestibular and motor trigeminal. In addition, a mapping of the neuropeptide Y-like immunoreactive fibers was carried out. Thus, the densest network of immunoreactive fibers was observed in the laminar spinal trigeminal nucleus. The nuclei periaqueductal gray, inferior central, praepositus hypoglossi, postpyramidal raphe, dorsal raphe, incertus and medial vestibular contained a moderate density of immunoreactive fibers, whereas the nuclei interpeduncularis, inferior colliculus, superior central, gracile, retrorubral, Kölliker-Fuse, dorsal tegmental, ambiguus and alaminar spinal trigeminal had the lowest density of neuropeptide Y-like immunoreactive fibers. The anatomical location of neuropeptide Y-like immunoreactivity suggests that the peptide could play an important role in several physiological functions, e.g., those involved in cardiovascular, auditory, motor, visual, nociceptive and somatosensory mechanisms.
Neuropeptides | 1992
M. de León; Rafael Coveñas; J.A. Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
We studied the distribution of somatostatin-28 (1-12)-immunoreactive fibers and cell bodies in the cat brainstem. A moderate density of cell bodies containing the peptide was observed in the ventral nucleus of the lateral lemniscus, accessory dorsal tegmental nucleus, retrofacial nucleus and in the lateral reticular nucleus, whereas a low density of such perikarya was found in the interpeduncular nucleus, nucleus incertus, nucleus sagulum, gigantocellular tegmental field, nucleus of the trapezoid body, nucleus praepositus hypoglosii, lateral and magnocellular tegmental fields, nucleus of the solitary tract, nucleus ambiguous and in the nucleus intercalatus. Moreover, a moderate density of somatostatin-28 (1-12)-immunoreactive processes was found in the dorsal nucleus of the raphe, dorsal tegmental nucleus, accessory dorsal tegmental nucleus, periaqueductal gray and in the marginal nucleus of the brachium conjunctivum. Finally, few immunoreactive fibers were visualized in the interpeduncular nucleus, cuneiform nucleus, locus coeruleus, nucleus incertus, superior and inferior central nuclei, nucleus sagulum, ventral nucleus of the lateral lemniscus, nucleus praepositus hypoglosii, medial vestibular nucleus, Kölliker-Fuse area, nucleus ambiguous, retrofacial nucleus, postpyramidal nucleus of the raphe, nucleus of the solitary tract, dorsal motor nucleus of the vagus, lateral reticular nucleus and laminar and alaminar spinal trigeminal nuclei.
Neuropeptides | 1991
M. de León; Rafael Coveñas; J.A. Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
Using an indirect immunoperoxidase technique, the location of somatostatin-28 (1-12)-like immunoreactive fibres and cell bodies in the cat diencephalon was studied. The hypothalamus was richer in somatostatin-28 (1-12)-like immunoreactive structures than the thalamus. A high density of immunoreactive fibres was observed in the nuclei habenularis lateralis, paraventricularis anterior (its caudal part), filiformis, hypothalami ventromedialis, and regio praeoptica, whereas a moderate density was found in the nuclei paracentralis, supraopticus, supra chiasmaticus, hypothalamus posterior and area hypothalamica dorsalis. The nuclei lateralis dorsalis, lateralis posterior, medialis dorsalis, rhomboidens, centralis medialis, ventralis medialis, reuniens, anterior dorsalis, parataenialis, interanteromedialis, hypothalamus lateralis, hypothalamus dorsomedialis and arcuatus had the lowest density of immunoreactive fibres. In addition, a high or moderate density of somatostatin-28 (1-12)-like immunoreactive cell bodies was observed in the nuclei paraventricularis hypothalami, supraopticus, supra chiasmaticus, area hypothalamics dorsalis, subparafascicularis, hypothalamus posterior and hypothalamus anterior, whereas scarce immunoreactive perikarya were visualized in the nuclei lateralis dorsalis and parafascicularis. The distribution of somatostatin-28 (1-12)-like immunoreactive structures is compared with the location of other neuropeptides in the cat diencephalon.
Anatomy and Embryology | 1999
Rafael Coveñas; M. de León; José Ángel Narváez; J.A. Aguirre; G. Tramu; S. González-Barón
Using an indirect immunoperoxidase technique, we studied the location of β-endorphin (1–27) fibres and cell bodies in the cat brainstem. The highest density of immunoreactive fibres was found in the lateral and medial parabrachial nuclei and in the locus coeruleus; a moderate density was observed in the periaqueductal gray and the central reticular nucleus, and a low density was observed in the interpeduncular nucleus, the nucleus incertus, the raphe pallidus nucleus, the paralemniscal reticular nucleus, the laterodorsal tegmental nucleus, the pericentral division of the dorsal tegmental nucleus and the lateral reticular nucleus. Immunoreactive neurons were observed in the superior central nucleus, the pericentral division of the dorsal tegmental nucleus, the interpeduncular nucleus, the nucleus incertus and the dorsal raphe nucleus. Our results point to a more widespread distribution of β-endorphin (1–27)-immunoreactive perikarya in the cat brainstem in comparison with previous studies carried out in the same region of other mammals. The distribution of β-endorphin (1–27)-immunoreactive fibres and perikarya is compared with the location of other neuropeptides in the cat brainstem. Moreover, our findings reveal that β-endorphin (1–27)-immunoreactive structures are widely distributed in the cat brainstem, suggesting that the peptide might be involved in several physiological functions.
Brain Behavior and Evolution | 1989
J.R. Alonso; Rafael Coveñas; J. Lara; R. Arévalo; M. de León; José Aijón
The distribution of tyrosine hydroxylase (TH)-like immunoreactivity in the olfactory bulb was studied in three species of teleosts, the tench Tinca tinca, the Mediterranean barbel Barbus meridionalis and the rainbow trout Salmo gairdneri, by using an indirect immunoperoxidase method. The antiserum used displayed a characteristic pattern of immunostaining in the three species, and four main conclusions can be drawn: (1) there is a large population of TH-like positive cell bodies and fibers in the olfactory bulb in fish, mainly in the granule cell and plexiform layers; (2) the immunolabeled cells are identified as granule cells, but only one group of granule cells is positive; (3) specific quantitative variations exist in the pattern of TH immunoreactivity, with use of the same fixative, antibody and localization method, among the three species studied, and (4) the pattern of TH immunoreactivity in the olfactory bulb in teleosts is completely different from that described previously in amniotes.
Neuropeptides | 1993
P. Marcos; Rafael Coveñas; M. de León; José Ángel Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
We have studied the distribution of neurokinin A-like immunoreactive cell bodies and fibers in the cat brainstem. The densest clusters of perikarya containing the peptide were observed in the periaqueductal gray, inferior colliculus, postpyramidal nucleus of the raphe, medial nucleus of the solitary tract and in the lateral reticular nucleus. By contrast, the interpeduncular nucleus, magnocellular part of the red nucleus, central tegmental field, cuneiform nucleus, dorsal tegmental nucleus, nucleus sagulum and the medial and inferior vestibular nuclei had the lowest density, whereas a moderate density of immunoreactive cell bodies was found in the superior colliculus, medial division of the dorsal nucleus of the raphe, nucleus incertus, locus coeruleus and in the Kölliker-Fuse area. The highest density of immunoreactive fibers was observed in the substantia nigra, periaqueductal gray, marginal nucleus of the brachium conjunctivum, medial vestibular nucleus, medial nucleus of the solitary tract, laminar spinal trigeminal nucleus, inferior colliculus, medial division of the dorsal nucleus of the raphe, locus coeruleus, dorsal tegmental nucleus and in the spinal trigeminal tract. A moderate density of immunoreactive fibers was found in the dorsal motor nucleus of the vagus and in the postpyramidal nucleus of the raphe and a low density in the cuneiform nucleus, Kölliker-Fuse area, nucleus sagulum, inferior and superior central nuclei, lateral reticular nucleus and in the lateral and magnocellular tegmental fields.
Peptides | 1991
M. de León; Rafael Coveñas; J.A. Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
Using an indirect immunoperoxidase technique, the location of neurotensin-like fibers and cell bodies was studied in the diencephalon of the cat. The findings showed that the hypothalamus is richer in neurotensin-like-immunoreactive structures than the thalamus, and that neurotensin-like-immunoreactive structures are more widely distributed in the hypothalamus than in the thalamus. A high density of immunoreactive fibers was observed in the hypothalamic regions, area hypothalamica dorsalis, hypothalamus posterior, nucleus (n.) filiformis and n. arcuatus, whereas a moderate density was found in the n. parafascicularis, n. paraventricularis anterior, hypothalamus lateralis, median eminence and n. paraventricularis hypothalami. Other diencephalic regions such as n. lateralis posterior, n. lateralis dorsalis, n. medialis dorsalis, n. habenularis lateralis, n. centrum medianum, n. rhomboidens, n. reuniens, hypothalamus anterior, n. supra chiasmaticus, hypothalamus ventromedialis, n. supraopticus and hypothalamus dorsomedialis had the lowest density of immunoreactive fibers. In addition, the densest clusters of neurotensin-like perikarya were found in the n. arcuatus, n. centralis medialis and hypothalamus posterior, whereas the n. medialis dorsalis, n. paraventricularis anterior, n. reuniens, hypothalamus lateralis and hypothalamus ventromedialis had the lowest density. In the n. lateralis dorsalis, n. supraopticus, area hypothalamica dorsalis and n. supra chiasmaticus the density of immunoreactive perikarya was moderate.
Neuropeptides | 1996
Rafael Coveñas; M. de León; José Ángel Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
Abstract The distribution of β-endorphin (1–27) immunoreactive cell bodies and fibres was studied in the diencephalon of the cat using an indirect immunoperoxidase technique. In the thalamus, almost all the immunoreactive fibres were found in the midline region and in nuclei located near the midline, whereas in the hypothalamus fibres containing β-endorphin (1–27) were visualized extending by the whole structure. The hypothalamus showed a higher density of β-endorphin (1–27) immunoreactive fibres than the thalamus, as well as immunoreactive cell bodies, since in the thalamus no β-endorphin (1–27) immunoreactive neuron was located. The densest network of immunoreactive fibres was observed in the epithalamus (nucleus periventricularis anterior) and in the hypothalamic nuclei arcuatus, hypothalami ventromedialis, suprachiasmaticus, periventricularis hypothalami, hypothalamus dorsomedialis, area hypothalamica dorsalis, hypothalamus anterior, filiformis, hypothalamus posterior and regio praeoptica. In the hypothalamus, a high density of perikarya containing β-endorphin (1–27) was observed in the nucleus arcuatus and a low density in the nucleus hypothalami ventromedialis. The distribution of β-endorphin (1–27) immunoreactive fibres and perikarya is compared with the location of other neuropeptides in the cat diencephalon. Our findings reveal that b-endorphin (1–27) immunoreactive structures are widely distributed in the cat diencephalon, suggesting that the peptide might be involved in several physiological functions.
Brain Research Bulletin | 1993
Almudena Velasco; M. de León; Rafael Coveñas; P. Marcos; José Ángel Narváez; G. Tramu; J.A. Aguirre; S. González-Barón
The distribution of neurokinin A-like immunoreactive cell bodies and fibers in the diencephalon of the cat was studied using an indirect immunoperoxidase technique. A high or moderate density of immunoreactive neurons was observed in the nuclei habenularis lateralis, medialis dorsalis, parafascicularis, hypothalamus posterior, area hypothalamica dorsalis, hypothalamus lateralis, periventricularis hypothalami, above the corpus mamillare, and in the perifornical area, whereas scarce immunoreactive perikarya were visualized in the nuclei reuniens, hypothalami ventromedialis, hypothalamus dorsomedialis, and mamillaris lateralis. The highest density of fibers containing neurokinin A was found in the nuclei periventricularis anterior, rhomboidens, centralis medialis, periventricularis hypothalami, and supraopticus. In the regio praeoptica, area hypothalamica dorsalis, hypothalamus posterior, and in the perifornical area a moderate density of immunoreactive fibers was observed, whereas the nuclei habenularis lateralis, medialis dorsalis, mamillaris lateralis, parataenialis, reuniens, habenularis medialis, filiformis, hypothalamus dorsomedialis, hypothalami ventromedialis, arcuatus, and suprachiasmaticus showed a low density of neurokinin A immunoreactive fibers.
Brain Research Bulletin | 1995
M. de León; J.A. Aguirre; Rafael Coveñas; José Ángel Narváez; S. González-Barón
The distribution of parvalbumin-immunoreactive cell bodies and fibers in the cat diencephalon has been analyzed by using the avidin-biotin immunoperoxidase technique. The thalamus showed a higher density of immunoreactive cell bodies than the hypothalamus. A high or moderate density of perikarya and a high density of fibers containing parvalbumin was observed in the nuclei lateralis posterior, lateralis dorsalis, pulvinar, corpus geniculatum laterale, reticularis, medialis dorsalis, centrum medianum, subparafascicularis, ventralis postero-medialis, ventralis postero-lateralis, habenularis medialis, parafascicularis, corpus geniculatum mediale, centralis lateralis, rhomboidens, reuniens, centralis medialis, ventralis medialis, ventralis lateralis, parataenialis, anterior ventralis, anterior medialis, ventralis anterior, hypothalamus posterior, corpus mamillare, area hypothalamica dorsalis, and in the nucleus suprachiasmaticus. Moreover, a high or moderate density of immunoreactive fibers and a low density of parvalbumin-immunoreactive cell bodies was observed in the nuclei periventricularis anterior, anterior dorsalis, habenularis lateralis, corpus geniculatum laterale (pars ventralis), periventricularis hypothalami, hypothalamus lateralis, hypothalamus anterior, and in the hypothalamus dorsomedialis.