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| Registros recuperados: 15 | |
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| Picanço-Diniz,D.L.W.; Valença,M.M.; Antunes-Rodrigues,J.. |
| In previous studies, we demonstrated biphasic purinergic effects on prolactin (PRL) secretion stimulated by an adenosine A2 agonist. In the present study, we investigated the role of the activation of adenosine A1 receptors by (R)-N6-(2-phenylisopropyl)adenosine (R-PIA) at the pituitary level in in vitro PRL secretion. Hemipituitaries (one per cuvette in five replicates) from adult male rats were incubated. Administration of R-PIA (0.001, 0.01, 0.1, 1, and 10 µM) induced a reduction of PRL secretion into the medium in a U-shaped dose-response curve. The maximal reduction was obtained with 0.1 µM R-PIA (mean ± SEM, 36.01 ± 5.53 ng/mg tissue weight (t.w.)) treatment compared to control (264.56 ± 15.46 ng/mg t.w.). R-PIA inhibition (0.01 µM = 141.97 ± 15.79... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cyclopentyltheophylline; Dibutyryl cAMP; R-PIA; Pertussis toxin; Cholera toxin. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2006001100013 |
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| Silva,L.E.C.M.; Castro,M.; Amaral,F.C.; Antunes-Rodrigues,J.; Elias,L.L.K.. |
| Estradiol participates in the control of energy homeostasis, as demonstrated by an increase in food intake and in body weight gain after ovariectomy in rats. In the present study, female Wistar rats (200-230 g, N = 5-15 per group), with free access to chow, were individually housed in metabolic cages. We investigated food intake, body weight, plasma leptin levels, measured by specific radioimmunoassay, and the hypothalamic mRNA expression of orexigenic and anorexigenic neuropeptides, determined by real-time PCR, in ovariectomized rats with (OVX+E) and without (OVX) estradiol cypionate treatment (10 µg/kg body weight, sc, for 8 days). Hormonal and mRNA expression were determined at pre-feeding and 4 h after food intake. OVX+E rats showed lower food intake,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Estradiol; Leptin; Orexigenic and anorexigenic neuropeptides; Hypothalamus. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010000800009 |
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| Antunes-Rodrigues,J.; Ruginsk,S.G.; Mecawi,A.S.; Margatho,L.O.; Cruz,J.C.; Vilhena-Franco,T.; Reis,W.L.; Ventura,R.R.; Reis,L.C.; Vivas,L.M.; Elias,L.L.K.. |
| Several forebrain and brainstem neurochemical circuitries interact with peripheral neural and humoral signals to collaboratively maintain both the volume and osmolality of extracellular fluids. Although much progress has been made over the past decades in the understanding of complex mechanisms underlying neuroendocrine control of hydromineral homeostasis, several issues still remain to be clarified. The use of techniques such as molecular biology, neuronal tracing, electrophysiology, immunohistochemistry, and microinfusions has significantly improved our ability to identify neuronal phenotypes and their signals, including those related to neuron-glia interactions. Accordingly, neurons have been shown to produce and release a large number of chemical... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hypothalamus; Gaseous neuromodulators; Neuropeptides; Endocannabinoids; Glial cells; Neurotransmitters. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2013000400327 |
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| Maués,L.A.L.; Macchi,B.M.; Crespo-López,M.E.; Nasciutti,L.E.; Picanço-Diniz,D.L.W.; Antunes-Rodrigues,J.; Nascimento,J.L.M. do. |
| Heavy metals, such as methylmercury, are key environmental pollutants that easily reach human beings by bioaccumulation through the food chain. Several reports have demonstrated that endocrine organs, and especially the pituitary gland, are potential targets for mercury accumulation; however, the effects on the regulation of hormonal release are unclear. It has been suggested that serum prolactin could represent a biomarker of heavy metal exposure. The aim of this study was to evaluate the effect of methylmercury on prolactin release and the role of the nitrergic system using prolactin secretory cells (the mammosomatotroph cell line, GH3B6). Exposure to methylmercury (0-100 μM) was cytotoxic in a time- and concentration-dependent manner, with an LC50... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mercury; Methylmercury; Prolactin; Oxidative stress; Pituitary; Nitric oxide. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015000800691 |
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| Ventura,R.R.; Gomes,D.A.; Reis,W.L.; Elias,L.L.K.; Castro,M.; Valença,M.M.; Carnio,E.C.; Rettori,V.; McCann,S.M.; Antunes-Rodrigues,J.. |
| The central nervous system plays an important role in the control of renal sodium excretion. We present here a brief review of physiologic regulation of hydromineral balance and discuss recent results from our laboratory that focus on the participation of nitrergic, vasopressinergic, and oxytocinergic systems in the regulation of water and sodium excretion under different salt intake and hypertonic blood volume expansion (BVE) conditions. High sodium intake induced a significant increase in nitric oxide synthase (NOS) activity in the medial basal hypothalamus and neural lobe, while a low sodium diet decreased NOS activity in the neural lobe, suggesting that central NOS is involved in the control of sodium balance. An increase in plasma concentrations in... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Vasopressin; Oxytocin; ANP; Nitric oxide; Blood volume expansion; Sodium diet. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002000900011 |
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| Picanço-Diniz,D.L.W.; Valença,M.M.; Favaretto,A.L.V.; McCann,S.M.; Antunes-Rodrigues,J.. |
| We investigated the participation of A1 or A2 receptors in the gonadotrope and their role in the regulation of LH and FSH secretion in adult rat hemipituitary preparations, using adenosine analogues. A dose-dependent inhibition of LH and FSH secretion was observed after the administration of graded doses of the R-isomer of phenylisopropyladenosine (R-PIA; 1 nM, 10 nM, 100 nM, 1 µM and 10 µM). The effect of R-PIA (10 nM) was blocked by the addition of 8-cyclopentyltheophylline (CPT), a selective A1 adenosine receptor antagonist, at the dose of 1 µM. The addition of an A2 receptor-specific agonist, 5-N-methylcarboxamidoadenosine (MECA), at the doses of 1 nM to 1 µM had no significant effect on LH or FSH secretion, suggesting the absence of this receptor... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adenosine; LH; FSH; A1 receptor; Anterior pituitary. |
| Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1999000900017 |
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| Picanço-Diniz,D.L.W.; Valença,M.M.; Favaretto,A.L.V.; Antunes-Rodrigues,J.. |
| We investigated the effects of adenosine on prolactin (PRL) secretion from rat anterior pituitaries incubated in vitro. The administration of 5-N-methylcarboxamidoadenosine (MECA), an analog agonist that preferentially activates A2 receptors, induced a dose-dependent (1 nM to 1 µM) increase in the levels of PRL released, an effect abolished by 1,3-dipropyl-7-methylxanthine, an antagonist of A2 adenosine receptors. In addition, the basal levels of PRL secretion were decreased by the blockade of cyclooxygenase or lipoxygenase pathways, with indomethacin and nordihydroguaiaretic acid (NDGA), respectively. The stimulatory effects of MECA on PRL secretion persisted even after the addition of indomethacin, but not of NDGA, to the medium. MECA was unable to... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adenosine; Prolactin; A2 receptor; Pituitary gland. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2002000700015 |
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| Registros recuperados: 15 | |
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