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61.
Recent advances in the endocrinology of puberty 总被引:4,自引:0,他引:4
62.
63.
Carmen Vidal Liliana Porras-Hurtado Raquel Cruz Joaquín Quiralte Victoria Cardona Carlos Colás Luisa F. Castillo Carmen Marcos Teresa Soto Raquel Lopez-Abad Dolores Hernández Maria Teresa Audicana Margarita Armisén Virginia Rodríguez Celsa Perez-Carral Esther Moreno Rosario Cabañes Mercè Corominas Antonio Parra Teófilo Lobera Dolores Quiñones Pedro Ojeda Ildefonso Luna María Torres Angel Carracedo 《The Journal of allergy and clinical immunology》2013
64.
Ane Murueta‐Goyena Rocío Del Pino Marta Galds Begoa Arana Marian Acera Mar Carmona‐Abelln Tamara Fernndez‐Valle Beatriz Tijero Olaia Lucas‐Jimnez Natalia Ojeda Naroa Ibarretxe‐Bilbao Javier Pea Jesus Cortes Unai Ayala Maitane Barrenechea Juan Carlos Gmez‐Esteban Iigo Gabilondo 《Annals of neurology》2021,89(1):165-176
65.
Vasoactive intestinal peptide induces the synthesis of the cholesterol side-chain cleavage enzyme complex in cultured rat ovarian granulosa cells. 下载免费PDF全文
W H Trzeciak C E Ahmed E R Simpson S R Ojeda 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(19):7490-7494
Vasoactive intestinal peptide (VIP) has been identified in ovarian nerves and stimulates steroid secretion from immature ovaries. To gain insight into its mechanism of action, the effect of VIP on the synthesis of the cholesterol side-chain cleavage enzyme complex was studied in ovarian granulosa cells from immature estrogen-primed rats. The cells were cultured for 48 hr in serum-free medium; the proteins were labeled with [35S]methionine; and the synthesis of cytochrome P-450, iron-sulfur protein, and NADPH:iron-sulfur protein reductase was evaluated by electrophoretic analysis after immunoisolation with polyclonal antibodies directed against the bovine adrenal enzymes. VIP at concentrations ranging from 0.001 to 1 microM stimulated 3- to 5-fold the synthesis of cytochrome P-450 and iron-sulfur protein. Peptide NH2-terminal histidine, COOH-terminal isoleucine, which has greater than 50% sequence homology of VIP, stimulated the synthesis of both proteins at approximately 50% of VIP effectiveness. Secretin, another member of the glucagon-secretin family of peptides, which has only 30% sequence homology to VIP, was without effect. Similar results were observed with the NADPH:iron-sulfur protein reductase. VIP-induced synthesis of the cholesterol side-chain cleavage enzyme complex was accompanied by a dose-related increase in cAMP accumulation and progestin formation. It is concluded that VIP regulates the synthesis of the ovarian cholesterol side-chain cleavage enzyme complex, which catalyzes the rate-limiting reaction in progesterone biosynthesis, and that the VIP effect is at least partially mediated through cAMP. It is suggested that a stimulatory action of VIP on the synthesis of ovarian progesterone may contribute to regulating the functional development of the ovary. 相似文献
66.
Sara García‐Jiménez German Bernal Fernández Maria Fernanda Martínez Salazar Antonio Monroy Noyola Cairo Toledano Jaimes Angelica Meneses Acosta Leticia Gonzalez Maya Elizabeth Aveleyra Ojeda Maria A. Terrazas Meraz Boll Marie‐Catherine Miguel A. Sánchez‐Alemán 《Journal of clinical laboratory analysis》2015,29(1):5-9
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Involvement of transforming growth factor alpha in the release of luteinizing hormone-releasing hormone from the developing female hypothalamus. 总被引:2,自引:1,他引:2 下载免费PDF全文
S R Ojeda H F Urbanski M E Costa D F Hill M Moholt-Siebert 《Proceedings of the National Academy of Sciences of the United States of America》1990,87(24):9698-9702
Little is known about the presence of trophic factors in the hypothalamus and the role they may play in regulating the functional development of hypothalamic neurons. We have investigated the ability of epidermal growth factor (EGF) and transforming growth factor alpha (TGF-alpha) to affect the release of luteinizing hormone-releasing hormone (LHRH), the neuropeptide that controls reproductive development. We have also determined whether the genes encoding EGF and TGF-alpha are expressed in the prepubertal female hypothalamus. Northern blot analysis of poly(A)+ RNA utilizing a single-stranded EGF cDNA probe failed to reveal the presence of EGF mRNA in either the hypothalamus or the cerebral cortex at any age studied (fetal day 18 to postnatal day 36). In contrast, both a complementary RNA probe and a double-stranded TGF-alpha cDNA recognized in these regions a 4.5-kilobase (kb) mRNA species identical to TGF-alpha mRNA. The abundance of TGF-alpha mRNA was 3-4 times greater in the hypothalamus than in the cerebral cortex. Both EGF and TGF-alpha (2-100 ng/ml) elicited a dose-related increase in LHRH release from the median eminence of juvenile rats in vitro. They also enhanced prostaglandin E2 (PGE2) release. The transforming growth factors TGF-beta 1 and -beta 2 were ineffective. Only a high dose of basic fibroblast growth factor was able to increase LHRH and PGE2 release. Blockade of the EGF receptor transduction mechanism with RG 50864, a selective inhibitor of EGF receptor tyrosine kinase activity, prevented the effect of both EGF and TGF-alpha on LHRH and PGE2 release but failed to inhibit the stimulatory effect of PGE2 on LHRH release. Inhibition of prostaglandin synthesis abolished the effect of TGF-alpha on LHRH, indicating that PGE2 mediates TGF-alpha-induced LHRH release. The results indicate that the effect of EGF and TGF-alpha on LHRH release is mediated by the EGF/TGF-alpha receptor and suggest that TGF-alpha rather than EGF may be the physiological ligand for this interaction. Since in the central nervous system most EGF/TGF-alpha receptors are located on glial cells, the results also raise the possibility that--at the median eminence--TGF-alpha action may involve a glial-neuronal interaction, a mechanism by which the trophic factor first stimulates PGE2 release from glial cells, and then PGE2 elicits LHRH from the neuronal terminals. 相似文献
69.
Enrico Poletti Lorenzo Azzalini Mohamed Ayoub Soledad Ojeda Carlo Zivelonghi Alessio La Manna Barbara Bellini Adrin Lostalo Aurora Luque Giuseppe Venuti Matteo Montorfano Pierfrancesco Agostoni Manuel Pan Mauro Carlino Kambis Mashayekhi 《Catheterization and cardiovascular interventions》2020,96(1):E45-E52
70.
Baloira A Núñez M Cifrian J Vilariño C Ojeda M Valverde D 《Archivos de bronconeumología》2012,48(3):77-80
Serotonin is a potent vasoconstrictor and pulmonary vascular growth factor whose concentration is increased in patients with pulmonary arterial hypertension (PAH). Its functions are mediated in part by the serotonin transporter protein (SERT) whose gene can have two allelic forms, both long (L) and short (S). The first was associated with greater function. 相似文献