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Rafael Coveñas - One of the best experts on this subject based on the ideXlab platform.
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distribution of alpha neoendorphin acth 18 39 and beta endorphin 1 27 in the alpaca brainstem
Anatomia Histologia Embryologia, 2018Co-Authors: Manuel Sanchez, Eliana De Souza, L.a. Aguilar, Rafael CoveñasAbstract:Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha-neoendorphin)- and pro-opiomelanocortin (adrenocorticotrophin hormone (18-39) (ACTH), beta-endorphin (1-27))-derived peptides. No peptidergic-immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha-neoendorphin, ACTH or beta-endorphin (1-27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro-opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha-neoendorphin (1-27)), 18.18% (for ACTH) and 13.95% (for beta-endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep-waking cycle and the control of pain transmission.
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Distribution of alpha‐neoendorphin, ACTH (18–39) and beta‐endorphin (1–27) in the alpaca brainstem
Anatomia Histologia Embryologia, 2018Co-Authors: Manuel Lisardo Sánchez, Eliana De Souza, L.a. Aguilar, Rafael CoveñasAbstract:Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha-neoendorphin)- and pro-opiomelanocortin (adrenocorticotrophin hormone (18-39) (ACTH), beta-endorphin (1-27))-derived peptides. No peptidergic-immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha-neoendorphin, ACTH or beta-endorphin (1-27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro-opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha-neoendorphin (1-27)), 18.18% (for ACTH) and 13.95% (for beta-endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep-waking cycle and the control of pain transmission.
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Immunohistochemical mapping of pro-opiomelanocortin- and pro-dynorphin-derived peptides in the alpaca (Lama pacos) diencephalon.
Journal of Chemical Neuroanatomy, 2014Co-Authors: Beatriz Manso, L E Medina, Zaida Díaz-cabiale, Manuel Lisardo Sánchez, L.a. Aguilar, Jose Angel Narvaez, Rafael CoveñasAbstract:Abstract Using an indirect immunoperoxidase technique, we studied the distribution of cell bodies and fibres containing non-opioid peptides (adrenocorticotropin hormone (ACTH), alpha-melanocyte-stimulating hormone) and opioid peptides (beta-endorphin (1–27), alpha-neo-endorphin, leucine-enkephalin) in the alpaca diencephalon. No immunoreactive cell bodies containing ACTH were found. Perikarya containing the other four peptides were observed exclusively in the hypothalamus and their distribution was restricted. Perikarya containing alpha-melanocyte-stimulating hormone or alpha-neo-endorphin showed a more widespread distribution than those containing leucine-enkephalin or beta-endorphin (1–27). Cell bodies containing pro-opiomelanocortin-derived peptides were observed in the arcuate nucleus, anterior and lateral hypothalamic areas and in the ventromedial and supraoptic hypothalamic nuclei, whereas perikarya containing alpha-neo-endorphin (a pro-dynorphin-derived peptide) were found in the arcuate nucleus, dorsal and lateral hypothalamic areas, and in the paraventricular, ventromedial and supraoptic hypothalamic nuclei. Immunoreactive cell bodies containing leucine-enkephalin were found in the lateral hypothalamic area and in the paraventricular hypothalamic nucleus. Immunoreactive fibres expressing pro-opiomelanocortin-derived peptides were more numerous than those expressing pro-dynorphin-derived peptides. A close anatomical relationship was observed: in all the diencephalic nuclei in which beta-endorphin (1–27)-immunoreactive fibres were found, fibres containing alpha-melanocyte-stimulating hormone or alpha-neo-endorphin were also observed. Fibres containing beta-endorphin (1–27), alpha-melanocyte-stimulating hormone or alpha-neo-endorphin were widely distributed throughout the diencephalon, but fibres containing ACTH or leucine-enkephalin showed a moderate distribution. The distribution of the five peptides studied here is also compared with that reported previously in other mammalian species. The widespread distribution observed indicates that both the pro-dynorphin and the pro-opiomelanocortin systems are involved in multiple physiological actions (e.g., food intake, thermoregulation, neuroendocrine and reproductive mechanisms) in the alpaca diencephalon.
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Mapping of alpha-neo-endorphin- and neurokinin B-immunoreactivity in the human brainstem
Brain Structure and Function, 2013Co-Authors: Ewing Duque, Zaida Díaz-cabiale, J.a. Narváez, Arturo Mangas, Pablo Salinas, Rafael CoveñasAbstract:We have studied the distribution of alpha-neo-endorphin- or neurokinin B-immunoreactive fibres and cell bodies in the adult human brainstem with no prior history of neurological or psychiatric disease. A low density of alpha-neo-endorphin-immunoreactive cell bodies was only observed in the medullary central gray matter and in the spinal trigeminal nucleus (gelatinosa part). Alpha-neo-endorphin-immunoreactive fibres were moderately distributed throughout the human brainstem. A high density of alpha-neo-endorphin-immunoreactive fibres was found only in the solitary nucleus (caudal part), in the spinal trigeminal nucleus (caudal part), and in the gelatinosa part of the latter nucleus. Neurokinin B-immunoreactive cell bodies (low density) were found in the periventricular central gray matter, the reticular formation of the pons and in the superior colliculus. The distribution of the neurokinin-immunoreactive fibres was restricted. In general, for both neuropeptides the density of the immunoreactive fibres was low. In the human brainstem, the proenkephalin system was more widely distributed than the prodynorphin system, and the preprotachykinin A system (neurokinin A) was more widely distributed than the preprotachykinin B system (neurokinin B).
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Neuropeptides in the raphe nuclei: an immunocytochemical study
Revista De Neurologia, 2001Co-Authors: Rafael Coveñas, M Belda, J.a. Aguirre, M. De Leon, P Marcos, Jose Angel Narvaez, Salvador González-barónAbstract:Introduction The raphe nuclei are involved in numerous mechanisms, included the antinociceptives. In the raphe nuclei of the cat, the distribution of neuropeptides is not very studied. Aim. To know the distribution of peptidergic fibers and cell bodies in the raphe nuclei of the cat. We studied a total of fifteen neuropeptides. Material and methods We used four control cats (without colchicine) and six with colchicine (administered into the Sylvian aqueduct). We used an indirect immunocytochemical technique. The histologic controls carried out confirm the specificity of the primary and secondary antibodies used. Results We observed in the fibers and/or the cell bodies located in the dorsal raphe nucleus a total of 14 neuropeptides, 12 in the raphe pallidus, 11 in the medial raphe, 10 in the raphe magnus, 8 in the raphe pontis and 7 in the raphe obscurus. We observed immunoreactive cell bodies in the raphe pallidus (with neurokinin A/leucine enkephalin), in the medial raphe (beta endorphin/alpha neo endorphin), in the raphe magnus (leucine enkephalin) and in the dorsal raphe (beta endorphin/alpha neo endorphin/methionine enkephalin Arg6 Gly7 Leu8/leucine enkephalin/neurokinin A/neurotensin). Conclusions 1. There are differences on the distribution of the peptidergic fibers/cell bodies observed in the raphe nuclei of the rat, the cat and the man; 2. The raphe nuclei could receive peptidergic afferences containing dynorphin A, galanin, neuropeptide Y, somatostatin ; 3. The cell bodies located in the medial raphe and containing beta endorphin or alpha neo endorphin could be projecting neurons; 4. There is a great functional complexity in the raphe nuclei due to the great number of neuropeptides observed in them; 5. The neuropeptides could interact between them, and 6. The neuropeptides located in the raphe nuclei could be involved in the control of the nociceptive information.
Richard G Allen - One of the best experts on this subject based on the ideXlab platform.
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post translational processing of proopiomelanocortin pomc in mouse pituitary melanotroph tumors induced by a pomc simian virus 40 large t antigen transgene
Journal of Biological Chemistry, 1993Co-Authors: Malcolm J Low, Bin Liu, Gary D Hammer, Marcelo Rubinstein, Richard G AllenAbstract:Abstract Mice harboring a transgene composed of proopiomelanocortin (POMC) gene promoter sequences (nucleotides -706 to +64) ligated to the simian virus (SV) 40 early gene encoding large T antigen developed large POMC-expressing pituitary tumors. Histologically the tumors arose from the intermediate lobe, contained nuclear SV40 T antigen and POMC peptides, but did not express other pituitary hormones. POMC processing in the pituitary tumors was indistinguishable from normal mouse intermediate lobe melanotrophs and was characterized by high proportions of acetylated and carboxyl-terminal shortened beta-endorphins, and amino-terminal acetylated alpha-melanocyte-stimulating hormone, and virtually no adrenocorticotropic hormone (ACTH)(1-39), beta-lipotropin, or POMC. The tumors contained abundant levels of mRNA for the prohormone convertase PC2 and undetectable levels of PC1. Normal mouse neurointermediate lobe also has a high ratio of PC2/PC1 expression that is distinct from the relative abundance of PC1 in anterior lobe and AtT-20 corticotroph cells. In contrast, extracts from tumors transplanted subcutaneously in nude mice contained predominantly nonacetylated forms of beta-endorphin(1-31) and -(1-27), very little ACTH(1-39), almost no corticotropin-like intermediate peptide or alpha-melanocyte-stimulating hormone, and higher proportions of intact POMC. Surprisingly, despite the less efficient proteolytic cleavage, a transplanted tumor expressed both PC1 and PC2. These studies are the first biochemical documentation of a melanotroph pituitary tumor in a rodent species and provide a new model for the investigation of pituitary oncogenesis and the molecular basis of tissue-specific prohormone post-translational processing.
Zaida Díaz-cabiale - One of the best experts on this subject based on the ideXlab platform.
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Immunohistochemical mapping of pro-opiomelanocortin- and pro-dynorphin-derived peptides in the alpaca (Lama pacos) diencephalon.
Journal of Chemical Neuroanatomy, 2014Co-Authors: Beatriz Manso, L E Medina, Zaida Díaz-cabiale, Manuel Lisardo Sánchez, L.a. Aguilar, Jose Angel Narvaez, Rafael CoveñasAbstract:Abstract Using an indirect immunoperoxidase technique, we studied the distribution of cell bodies and fibres containing non-opioid peptides (adrenocorticotropin hormone (ACTH), alpha-melanocyte-stimulating hormone) and opioid peptides (beta-endorphin (1–27), alpha-neo-endorphin, leucine-enkephalin) in the alpaca diencephalon. No immunoreactive cell bodies containing ACTH were found. Perikarya containing the other four peptides were observed exclusively in the hypothalamus and their distribution was restricted. Perikarya containing alpha-melanocyte-stimulating hormone or alpha-neo-endorphin showed a more widespread distribution than those containing leucine-enkephalin or beta-endorphin (1–27). Cell bodies containing pro-opiomelanocortin-derived peptides were observed in the arcuate nucleus, anterior and lateral hypothalamic areas and in the ventromedial and supraoptic hypothalamic nuclei, whereas perikarya containing alpha-neo-endorphin (a pro-dynorphin-derived peptide) were found in the arcuate nucleus, dorsal and lateral hypothalamic areas, and in the paraventricular, ventromedial and supraoptic hypothalamic nuclei. Immunoreactive cell bodies containing leucine-enkephalin were found in the lateral hypothalamic area and in the paraventricular hypothalamic nucleus. Immunoreactive fibres expressing pro-opiomelanocortin-derived peptides were more numerous than those expressing pro-dynorphin-derived peptides. A close anatomical relationship was observed: in all the diencephalic nuclei in which beta-endorphin (1–27)-immunoreactive fibres were found, fibres containing alpha-melanocyte-stimulating hormone or alpha-neo-endorphin were also observed. Fibres containing beta-endorphin (1–27), alpha-melanocyte-stimulating hormone or alpha-neo-endorphin were widely distributed throughout the diencephalon, but fibres containing ACTH or leucine-enkephalin showed a moderate distribution. The distribution of the five peptides studied here is also compared with that reported previously in other mammalian species. The widespread distribution observed indicates that both the pro-dynorphin and the pro-opiomelanocortin systems are involved in multiple physiological actions (e.g., food intake, thermoregulation, neuroendocrine and reproductive mechanisms) in the alpaca diencephalon.
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Mapping of alpha-neo-endorphin- and neurokinin B-immunoreactivity in the human brainstem
Brain Structure and Function, 2013Co-Authors: Ewing Duque, Zaida Díaz-cabiale, J.a. Narváez, Arturo Mangas, Pablo Salinas, Rafael CoveñasAbstract:We have studied the distribution of alpha-neo-endorphin- or neurokinin B-immunoreactive fibres and cell bodies in the adult human brainstem with no prior history of neurological or psychiatric disease. A low density of alpha-neo-endorphin-immunoreactive cell bodies was only observed in the medullary central gray matter and in the spinal trigeminal nucleus (gelatinosa part). Alpha-neo-endorphin-immunoreactive fibres were moderately distributed throughout the human brainstem. A high density of alpha-neo-endorphin-immunoreactive fibres was found only in the solitary nucleus (caudal part), in the spinal trigeminal nucleus (caudal part), and in the gelatinosa part of the latter nucleus. Neurokinin B-immunoreactive cell bodies (low density) were found in the periventricular central gray matter, the reticular formation of the pons and in the superior colliculus. The distribution of the neurokinin-immunoreactive fibres was restricted. In general, for both neuropeptides the density of the immunoreactive fibres was low. In the human brainstem, the proenkephalin system was more widely distributed than the prodynorphin system, and the preprotachykinin A system (neurokinin A) was more widely distributed than the preprotachykinin B system (neurokinin B).
Lex Nagelkerken - One of the best experts on this subject based on the ideXlab platform.
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Identification of two moieties of ß-endorphin with opposing effects on rat T-cell proliferation
Immunology, 1993Co-Authors: P. Van Den Bergh, Jan Rozing, Lex NagelkerkenAbstract:In a previous study we demonstrated that beta-endorphin (beta-end) may stimulate rat T-cell proliferation via triggering of non-opioid receptors, whereas this stimulatory effect is abrogated by interaction of beta-end with opioid receptors. In the present study we provide evidence for this dualistic nature of beta-end by the identification of stimulatory and inhibitory sites of beta-end with the use of peptide fragments. The fragments beta-end6-31 and beta-end 18-31, which both lack the opioid receptor binding N-terminal sequence, enhanced rat T-cell proliferation when added directly to the cultures. By contrast, the peptide fragments beta-end24-31 and beta-end28-31 did not stimulate proliferation. Peptides and fragments containing the N-terminal part, i.e. methionine-enkephalin (met-enk), Alpha-Endorphin (alpha-end), gamma-endorphin, the fragment beta-end1-27, and the intact beta-end, did not influence proliferation by themselves. However, the addition of met-enk or alpha-end to T cells that had been stimulated by the fragments beta-end6-31 or beta-end18-31 resulted in the abrogation of the stimulating effect. These data further support the hypothesis that beta-end is a peptide with a dualistic nature: its C-terminal moiety enhances T-cell proliferation, whereas this stimulatory effect can be prevented by peptides that possess the N-terminal enkephalin sequence.
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Two opposing modes of action of beta-endorphin on lymphocyte function.
Immunology, 1991Co-Authors: P. Van Den Bergh, Jan Rozing, Lex NagelkerkenAbstract:: Five opioid peptides (alpha-, beta-, and gamma-endorphin, methionine- and leucine-enkephalin) were tested for their effect on the concanavalin A-induced proliferative response of splenocytes of adult male F344 rats. The continuous presence of these opioid peptides during culture of T cells did not affect proliferation. However, 30 min of preincubation with beta-endorphin (beta-end), but not with the other opioid peptides, resulted in a dose-dependent enhancement of proliferation of 50-100%. This potentiating effect of beta-end on proliferation was preceded by an increase in the production of interleukin-2 (IL-2) and in the extent of IL-2 receptor expression. The stimulatory effect of beta-end was not prevented by naloxone, indicating that classical opioid receptors were not involved. The continuous presence of beta-end (or alpha-end) in cultures of cells that had been preincubated with beta-end completely abolished the stimulatory effect, pointing towards the potential of beta-end to regulate T-cell function via different mechanisms.
Katalin Sz. Szalay - One of the best experts on this subject based on the ideXlab platform.
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Effects of pro-opiomelanocortin peptides on adrenocortical steroidogenesis.
The Journal of steroid biochemistry and molecular biology, 1993Co-Authors: Katalin Sz. SzalayAbstract:Whilst studying the effects of pro-opiomelanocortin (POMC) peptides on adrenocortical steroidogenesis we showed that alpha-melanocyte-stimulating hormone (alpha-MSH) has a specific glomerulotropic effect and potentiates both the mineralocorticotropic and glucocorticotropic effects of ACTH. The fragments ACTH-(4-10) and ACTH-(11-13) are responsible for the glomerulotropic effect of alpha-MSH. beta-Endorphin enhances, inhibits or has no effect on corticosteroidogenesis, depending on the dose and on the functional state of the adrenocortical cells (saturation of the receptors). beta-Endorphin antagonizes the effect of alpha-MSH on aldosterone production. It is suggested that the modulatory effects of POMC peptides on adrenocortical steroidogenesis may be of physiological significance.
