Luciano Debeljuk - Academia.edu (original) (raw)
Papers by Luciano Debeljuk
Archives of Andrology, 1983
The effect of chronic treatment with a y-aminobutyric acid (GABA)-mimetic compound, progabide, an... more The effect of chronic treatment with a y-aminobutyric acid (GABA)-mimetic compound, progabide, and an inhibitor of GABA-transaminase, yacetylenic GABA (GAG), was tested in prepubertal male rats. The effect of ybutyrolactone (GBL), given orally, was also tested. The rats treated with progabide did not show any difference in body, testicular, or seminal vesicle weights or serum prolactin levels, as compared with control rats. Treatment with GAG, at both dose levels used, did not significantly affect body weight. Testicular weight was significantly lower in the group of rats treated with the low dosage of GAG (5 mgikg), and serum prolactin was significantly lower in the rats treated with the high dosage of GAG (20 mg/kg) as compared with control rats. In the first experiment performed with GBL, the rats given this compound had significantly lower body and testicular weights as compared with control rats. In the second experiment, GBL-treated rats had body weights similar to those of control rats, but testicular weights were significantly decreased. Prolonged treatment with GABA mimetics may affect the hypothalamic-pituitary-testicular axis.
Endocrine, 1999
In this investigation, the neuroendocrine alterations induced by high, chronic circulating levels... more In this investigation, the neuroendocrine alterations induced by high, chronic circulating levels of endogenous growth hormone (GH) were studied in transgenic mice with ectopic overexpression of the human growth hormone-releasing hormone (h-GH-RH) gene. In comparison with their normal littermates, transgenic h-GH-RH mice had elevated plasma levels of GH, prolactin (PRL), and corticosterone. In addition, they had elevated body, liver, kidney, spleen, and pituitary weights compared with normal mice. Testis and seminal vesicle weights were also increased in transgenic mice. Although basal plasma luteinizing hormone (LH) levels, plasma estradiol levels in females, and plasma testosterone levels in males did not differ significantly between normal and transgenic animals, the LH response to castration was severely impaired in transgenic mice of both sexes. Among the biogenic amines studied in the hypothalamus, only dopamine concentrations were significantly lower in transgenic animals compared with their normal littermates. This decrease in hypothalamic dopamine may be related to the hyperprolactinemia in transgenic animals. In vitro, pituitaries from transgenic mice released significantly higher amounts of GH, and although the basal release of LH was not different in both normal and transgenic mice, the response to gonadotropin-releasing hormone was significantly smaller in transgenic mice. Cultured anterior pituitary cells from transgenic mice secreted high quantities of GH and PRL in vitro, but these quantities significantly decreased from 1 to 8 wk in culture.These results show that high, persistent levels of circulating endogenous GH induce alterations in neuroendocrine functions related to the hypothalamopituitary-gonadal and the hypothalamo-pituitaryadrenal axes.
Neuroendocrinology, 1987
All rights reserved. No part of this publication maybe translated intoother languages, repro duce... more All rights reserved. No part of this publication maybe translated intoother languages, repro duced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the pub lisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center (see 'Information for Readers and Sub scribers').
Reproduction, 1994
In this investigation the concentrations of immunoreactive substance P and neurokinin A in the hy... more In this investigation the concentrations of immunoreactive substance P and neurokinin A in the hypothalamus and anterior pituitary of the Siberian hamster were compared with those in the rat and Syrian hamster. The concentrations of immunoreactive neurokinin A in the hypothalamus of Siberian hamsters were significantly higher than those of rats and Syrian hamsters, while male Siberian hamsters had similar amounts of substance P in the hypothalamus to those of male Syrian hamsters, but had higher amounts than those in male rats. However, female Siberian hamsters had significantly higher hypothalamic concentrations of both substance P and neurokinin A than did female Syrian hamsters and rats. In the anterior pituitary glands of Siberian hamsters, concentrations of substance P and neurokinin A were markedly higher than they were in rats and even more so than in Syrian hamsters. Ovariectomy further increased tachykinin concentrations in the anterior pituitary gland of female Siberian hamsters, and this was completely prevented by oestradiol replacement. Female Siberian hamsters kept under conditions of reduced photoperiod had significantly higher tachykinin concentrations in the anterior pituitary than did animals kept under daily photoperiods of 16 h light:8 h dark. The incubation of anterior pituitaries from female Siberian hamsters with a neurokinin A receptor antagonist resulted in a partial blockade of the LH and FSH release in response to LHRH. Thus, the high concentration of tachykinins present in the anterior pituitary of the Siberian hamster may have a local role in modulating the secretion or release of gonadotrophins.
Peptides, 2002
Mammalian neurokinin A (NKA) and substance P (SP) are neuropeptides widely distributed in the bod... more Mammalian neurokinin A (NKA) and substance P (SP) are neuropeptides widely distributed in the body; they are potential regulators of the basal blood flow and therefore of the function of many organs and tissues. In the present investigation, we studied the age-dependent changes in NKA and SP in ovary, liver, pancreas and spleen as well as the role of exogenous melatonin on these changes. Female rats of 5, 15 or 25 months of age were studied. In the ovary, NKA concentrations did not change during aging. SP concentrations in the control group were significantly higher (P < 0.01) in old rats than in the other two age groups studied. Melatonin treatment resulted in reduced concentrations as compared with those of the control old rats. In the pancreas, NKA and SP concentrations increased during aging, the young rats showing significantly lower values (P < 0.01) than middle-aged and old rats for NKA and significantly lower (P < 0.01) than the old rats for SP. After melatonin treatment the differences in NKA concentrations disappeared and SP decreased in middle-aged as compared with those in old rats. In the liver, NKA and SP concentrations in the control and melatonin-treated groups did not differ significantly for the three age groups studied. Splenic NKA in control and melatonin-treated groups increased from young to middle-age up to old ages. SP concentrations showed similar values at all ages except in melatonin-treated old rats; in these animals there were significantly higher concentrations than in young melatonin-treated rats. The effect of melatonin was mainly observed on the ovary and pancreas in old rats, with a reduction in the concentrations as compared with those observed in the young groups.
Reproduction, 1976
Recent reports have demonstrated that oestradiol modifies the pituitary response to LH-RH (Debelj... more Recent reports have demonstrated that oestradiol modifies the pituitary response to LH-RH (Debeljuk, Arimura & Schally, 1972; Debeljuk, Vilchez Martinez, Arimura & Schally, 1974). This effect of oestradiol is biphasic, being inhibitory between 2 and 6 hr after its administration, but stimulatory after 9 hr (Vilchez Martinez, Arimura, Debeljuk & Schally, 1974). Similar results in different experimental conditions have been reported by Libertun, Orias & McCann (1974) and Van Dieten, Steijsiger, Dullaart & Van Rees (1974). We have recently shown that actinomycin D was able to block the augmenting effect of oestradiol on the pituitary response to LH-RH in neonatally androgenized rats (Debeljuk, Rettori, Rozados & Villegas V\l=e'\lez,1974). In the present report, the effects of actinomycin D were similarly investigated, but in normal dioestrous rats. Materials and methods Female rats of the Wistar strain (mean weight : 180 g) were used. They were maintained on a diet of laboratory chow and vegetables, and with free access to water. The light schedule was 14 hr light/24 hr. The stage of the oestrous cycle was checked every day by observation of the vaginal cytology for at least 3 cycles. Only rats with regular 4-day cycles were selected. Rats on the first day of dioestrus were separated into 4 groups of 12 animals each, and given one of the following treatments: Group 1, corn oil; Group 2, oestradiol benzoate, dissolved in corn oil, and injected s.c. at a dose of 20 µg/rat; Group 3, oestradiol benzoate (20 ug/rat) plus actinomycin D (Lyovac Cosmegen: Merck, Sharp &
Cytogenetic and Genome Research, 1987
This index covers the abstracts but not the committee reports contained in this volume. Entries a... more This index covers the abstracts but not the committee reports contained in this volume. Entries arc listed alphabetically by HGM Workshop symbols. All mapped human genes, markers and fragile sites are listed by HGM Work shop symbol in the Catalog (Table I) and by full name in Table II. All mapped DNA segments are listed in the tables of the Committee on human gene mapping by recombinant DNA techniques. For additional information please refer to the appropriate committee reports. This index lists only human genes. For non-human genes please refer to the report of the Committee on comparative mapping. For chromosome rearrangements associated with neoplasia please refer to the report of the Committee on structural chromosome changes in neoplasia, and for fragile sites to the report of the Committee on cytogenetic markers.
Peptides, 2002
Previous data showed that aging of the central nervous system (CNS) is associated with widespread... more Previous data showed that aging of the central nervous system (CNS) is associated with widespread changes in tachykinin gene expression. However, there are no data about the possible role of exogenous melatonin in modulating the tachykinergic system during aging. The aim of this work was to analyze the age-dependent changes on neurokinin A (NKA) and substance P (SP) levels in
Peptides, 1992
The effects of neonatal administration of monosodium glutamate (MSG) and castration on hypothalam... more The effects of neonatal administration of monosodium glutamate (MSG) and castration on hypothalamic and anterior pituitary levels of neurokinin A (NKA) were studied in male and female rats killed at 46 days of age. In male rats treated neonatally with MSG, body, anterior pituitary, testis, ...
Endocrinology, 1991
Immunoneutralization of endogenous neuropeptide Y (NPY) with specific antibodies was used to eval... more Immunoneutralization of endogenous neuropeptide Y (NPY) with specific antibodies was used to evaluate the possible physiological role of this neuropeptide in the regulation of gonadotropin and PRL secretion in the mouse. Because regulation of anterior pituitary function can be ...
Archives of Andrology, 1983
The effect of chronic treatment with a y-aminobutyric acid (GABA)-mimetic compound, progabide, an... more The effect of chronic treatment with a y-aminobutyric acid (GABA)-mimetic compound, progabide, and an inhibitor of GABA-transaminase, yacetylenic GABA (GAG), was tested in prepubertal male rats. The effect of ybutyrolactone (GBL), given orally, was also tested. The rats treated with progabide did not show any difference in body, testicular, or seminal vesicle weights or serum prolactin levels, as compared with control rats. Treatment with GAG, at both dose levels used, did not significantly affect body weight. Testicular weight was significantly lower in the group of rats treated with the low dosage of GAG (5 mgikg), and serum prolactin was significantly lower in the rats treated with the high dosage of GAG (20 mg/kg) as compared with control rats. In the first experiment performed with GBL, the rats given this compound had significantly lower body and testicular weights as compared with control rats. In the second experiment, GBL-treated rats had body weights similar to those of control rats, but testicular weights were significantly decreased. Prolonged treatment with GABA mimetics may affect the hypothalamic-pituitary-testicular axis.
Endocrine, 1999
In this investigation, the neuroendocrine alterations induced by high, chronic circulating levels... more In this investigation, the neuroendocrine alterations induced by high, chronic circulating levels of endogenous growth hormone (GH) were studied in transgenic mice with ectopic overexpression of the human growth hormone-releasing hormone (h-GH-RH) gene. In comparison with their normal littermates, transgenic h-GH-RH mice had elevated plasma levels of GH, prolactin (PRL), and corticosterone. In addition, they had elevated body, liver, kidney, spleen, and pituitary weights compared with normal mice. Testis and seminal vesicle weights were also increased in transgenic mice. Although basal plasma luteinizing hormone (LH) levels, plasma estradiol levels in females, and plasma testosterone levels in males did not differ significantly between normal and transgenic animals, the LH response to castration was severely impaired in transgenic mice of both sexes. Among the biogenic amines studied in the hypothalamus, only dopamine concentrations were significantly lower in transgenic animals compared with their normal littermates. This decrease in hypothalamic dopamine may be related to the hyperprolactinemia in transgenic animals. In vitro, pituitaries from transgenic mice released significantly higher amounts of GH, and although the basal release of LH was not different in both normal and transgenic mice, the response to gonadotropin-releasing hormone was significantly smaller in transgenic mice. Cultured anterior pituitary cells from transgenic mice secreted high quantities of GH and PRL in vitro, but these quantities significantly decreased from 1 to 8 wk in culture.These results show that high, persistent levels of circulating endogenous GH induce alterations in neuroendocrine functions related to the hypothalamopituitary-gonadal and the hypothalamo-pituitaryadrenal axes.
Neuroendocrinology, 1987
All rights reserved. No part of this publication maybe translated intoother languages, repro duce... more All rights reserved. No part of this publication maybe translated intoother languages, repro duced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the pub lisher or, in the case of photocopying, direct payment of a specified fee to the Copyright Clearance Center (see 'Information for Readers and Sub scribers').
Reproduction, 1994
In this investigation the concentrations of immunoreactive substance P and neurokinin A in the hy... more In this investigation the concentrations of immunoreactive substance P and neurokinin A in the hypothalamus and anterior pituitary of the Siberian hamster were compared with those in the rat and Syrian hamster. The concentrations of immunoreactive neurokinin A in the hypothalamus of Siberian hamsters were significantly higher than those of rats and Syrian hamsters, while male Siberian hamsters had similar amounts of substance P in the hypothalamus to those of male Syrian hamsters, but had higher amounts than those in male rats. However, female Siberian hamsters had significantly higher hypothalamic concentrations of both substance P and neurokinin A than did female Syrian hamsters and rats. In the anterior pituitary glands of Siberian hamsters, concentrations of substance P and neurokinin A were markedly higher than they were in rats and even more so than in Syrian hamsters. Ovariectomy further increased tachykinin concentrations in the anterior pituitary gland of female Siberian hamsters, and this was completely prevented by oestradiol replacement. Female Siberian hamsters kept under conditions of reduced photoperiod had significantly higher tachykinin concentrations in the anterior pituitary than did animals kept under daily photoperiods of 16 h light:8 h dark. The incubation of anterior pituitaries from female Siberian hamsters with a neurokinin A receptor antagonist resulted in a partial blockade of the LH and FSH release in response to LHRH. Thus, the high concentration of tachykinins present in the anterior pituitary of the Siberian hamster may have a local role in modulating the secretion or release of gonadotrophins.
Peptides, 2002
Mammalian neurokinin A (NKA) and substance P (SP) are neuropeptides widely distributed in the bod... more Mammalian neurokinin A (NKA) and substance P (SP) are neuropeptides widely distributed in the body; they are potential regulators of the basal blood flow and therefore of the function of many organs and tissues. In the present investigation, we studied the age-dependent changes in NKA and SP in ovary, liver, pancreas and spleen as well as the role of exogenous melatonin on these changes. Female rats of 5, 15 or 25 months of age were studied. In the ovary, NKA concentrations did not change during aging. SP concentrations in the control group were significantly higher (P < 0.01) in old rats than in the other two age groups studied. Melatonin treatment resulted in reduced concentrations as compared with those of the control old rats. In the pancreas, NKA and SP concentrations increased during aging, the young rats showing significantly lower values (P < 0.01) than middle-aged and old rats for NKA and significantly lower (P < 0.01) than the old rats for SP. After melatonin treatment the differences in NKA concentrations disappeared and SP decreased in middle-aged as compared with those in old rats. In the liver, NKA and SP concentrations in the control and melatonin-treated groups did not differ significantly for the three age groups studied. Splenic NKA in control and melatonin-treated groups increased from young to middle-age up to old ages. SP concentrations showed similar values at all ages except in melatonin-treated old rats; in these animals there were significantly higher concentrations than in young melatonin-treated rats. The effect of melatonin was mainly observed on the ovary and pancreas in old rats, with a reduction in the concentrations as compared with those observed in the young groups.
Reproduction, 1976
Recent reports have demonstrated that oestradiol modifies the pituitary response to LH-RH (Debelj... more Recent reports have demonstrated that oestradiol modifies the pituitary response to LH-RH (Debeljuk, Arimura & Schally, 1972; Debeljuk, Vilchez Martinez, Arimura & Schally, 1974). This effect of oestradiol is biphasic, being inhibitory between 2 and 6 hr after its administration, but stimulatory after 9 hr (Vilchez Martinez, Arimura, Debeljuk & Schally, 1974). Similar results in different experimental conditions have been reported by Libertun, Orias & McCann (1974) and Van Dieten, Steijsiger, Dullaart & Van Rees (1974). We have recently shown that actinomycin D was able to block the augmenting effect of oestradiol on the pituitary response to LH-RH in neonatally androgenized rats (Debeljuk, Rettori, Rozados & Villegas V\l=e'\lez,1974). In the present report, the effects of actinomycin D were similarly investigated, but in normal dioestrous rats. Materials and methods Female rats of the Wistar strain (mean weight : 180 g) were used. They were maintained on a diet of laboratory chow and vegetables, and with free access to water. The light schedule was 14 hr light/24 hr. The stage of the oestrous cycle was checked every day by observation of the vaginal cytology for at least 3 cycles. Only rats with regular 4-day cycles were selected. Rats on the first day of dioestrus were separated into 4 groups of 12 animals each, and given one of the following treatments: Group 1, corn oil; Group 2, oestradiol benzoate, dissolved in corn oil, and injected s.c. at a dose of 20 µg/rat; Group 3, oestradiol benzoate (20 ug/rat) plus actinomycin D (Lyovac Cosmegen: Merck, Sharp &
Cytogenetic and Genome Research, 1987
This index covers the abstracts but not the committee reports contained in this volume. Entries a... more This index covers the abstracts but not the committee reports contained in this volume. Entries arc listed alphabetically by HGM Workshop symbols. All mapped human genes, markers and fragile sites are listed by HGM Work shop symbol in the Catalog (Table I) and by full name in Table II. All mapped DNA segments are listed in the tables of the Committee on human gene mapping by recombinant DNA techniques. For additional information please refer to the appropriate committee reports. This index lists only human genes. For non-human genes please refer to the report of the Committee on comparative mapping. For chromosome rearrangements associated with neoplasia please refer to the report of the Committee on structural chromosome changes in neoplasia, and for fragile sites to the report of the Committee on cytogenetic markers.
Peptides, 2002
Previous data showed that aging of the central nervous system (CNS) is associated with widespread... more Previous data showed that aging of the central nervous system (CNS) is associated with widespread changes in tachykinin gene expression. However, there are no data about the possible role of exogenous melatonin in modulating the tachykinergic system during aging. The aim of this work was to analyze the age-dependent changes on neurokinin A (NKA) and substance P (SP) levels in
Peptides, 1992
The effects of neonatal administration of monosodium glutamate (MSG) and castration on hypothalam... more The effects of neonatal administration of monosodium glutamate (MSG) and castration on hypothalamic and anterior pituitary levels of neurokinin A (NKA) were studied in male and female rats killed at 46 days of age. In male rats treated neonatally with MSG, body, anterior pituitary, testis, ...
Endocrinology, 1991
Immunoneutralization of endogenous neuropeptide Y (NPY) with specific antibodies was used to eval... more Immunoneutralization of endogenous neuropeptide Y (NPY) with specific antibodies was used to evaluate the possible physiological role of this neuropeptide in the regulation of gonadotropin and PRL secretion in the mouse. Because regulation of anterior pituitary function can be ...