Características da interação da serotonina com receptores serotoninérgicos e adrenérgicos em ducto deferente de rato

BV UNIFESP: Teses e dissertaçõe

Evidence for the participation of calcium in non-genomic relaxations induced by androgenic steroids in rat vas deferens

Background and purpose: Androgens cause non-genomic relaxation in several smooth muscle preparations. However, such an effect has not been investigated in rat vas deferens yet. Our purpose was to study the effect of testosterone and derivatives in this tissue.Experimental approach: the influence of androgens was tested on contraction and translocation of intracellular Ca2+ induced by KCl in rat vas deferens in vitro.Key results: the testosterone derivative 5 alpha-dihydrotestosterone produced a rapid and reversible concentration-dependent relaxation of KCl-induced contractions. Other androgens were also effective, showing the following rank order of potency: androsterone >5 beta-dihydrotestosterone >androstenedione >5 alpha-dihydrotestosterone >testosterone. Calcium-induced contractions were also inhibited (about 45%) by 5 alpha-dihydrotestosterone (30 mu M). Moreover 5 alpha-dihydrotestosterone blocked the increase of intracellular Ca2+ induced by KCl, measured by the fluorescent dye fura-2. Relaxation to 5 alpha-dihydrotestosterone was resistant to the K+ channel antagonists glibenclamide, 4-aminopyridine and charybdotoxin. It was not affected by removal of epithelium or by L-NNA (300 mM), an inhibitor of nitric oxide biosynthesis, nor by selective inhibitors of soluble guanylate cyclase, ODQ or LY 83583, indicating that nitrergic or cGMP mediated mechanisms were not involved. the androgen-induced relaxation was also not blocked by the protein synthesis inhibitor cycloheximide (300 mu M) or by the classical androgen receptor flutamide (up to 100 mu M), corroborating that the effect is non-genomic.Conclusions and implications: Testosterone derivatives caused relaxation of the rat vas deferens, that did not involve epithelial tissue, K+ channels, or nitric oxide-dependent mechanisms, but was related to a partial blockade of Ca2+ influx.Universidade Federal de São Paulo, Dept Pharmacol, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pharmacol, BR-04044020 São Paulo, BrazilWeb of Scienc

NAADP-sensitive two-pore channels are present and functional in gastric smooth muscle cells

Nicotinic acid adenine dinucleotide phosphate (NAADP) has been identified as an important modulator of Ca2+ release from the endo-lysosomal system in a variety of cells by a new and ubiquitous class of endo-lysosomal ion channels known as the two-pore channels (TPCs). However, the role of TPCs in NAADP action in smooth muscle is not known. in the present work, we investigated the effects of NAADP in gastric smooth muscle cells and its ability to release Ca2+ by TPCs. We show that Ca2+ signals mediated by NAADP were inhibited by disrupting Ca2+ handling by either acidic organelles (using bafilomycin A1) or the Endoplasmic Reticulum (using thapsigargin, ryanodine or 2-APB). Transcripts for endogenous TPC1 and TPC2 were readily detected and recombinant TPCs localized to the endosomes and/or lysosomes. Overexpression of wild-type TPCs but not pore mutants enhanced NAADP-mediated cytosolic Ca2+ signals. Desensitizing the NAADP pathway inhibited Ca2+-responses to extracellular stimulation with carbachol but not ATP. Taken together, these results indicate that NAADP likely induces Ca2+ release from the endolysosomal system through TPCs which is subsequently amplified via the ER in an agonist-specific manner. Thus, we suggest a second messenger role for NAADP in smooth muscle cells. (C) 2014 Elsevier B.V. All rights reserved.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Biotechnology and Biological Sciences Research CouncilFed Univ São Paulo UNIFESP, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Interdisciplinary Ctr Gene Therapy, BR-04044020 São Paulo, BrazilUniv Oxford, Dept Pharmacol, Oxford OX1 3QT, EnglandUCL, Dept Cell & Dev Biol, London, EnglandFed Univ São Paulo UNIFESP, Dept Pharmacol, São Paulo, BrazilUniversidade Federal de São Paulo, Interdisciplinary Ctr Gene Therapy, BR-04044020 São Paulo, BrazilFAPESP: 2008/11.515-3CNPq: 482030/2010-0CAPES: BB/G013721/1Web of Scienc

Nicotinic Acid Adenine Dinucleotide Phosphate (NAADP) Regulates Autophagy in Cultured Astrocytes

Nicotinic acid adenine dinucleotide phosphate (NAADP) is a potent Ca(2+)-mobilizing messenger that in many cells releases Ca(2+) from the endolysosomal system. Recent studies have shown that NAADP-induced Ca(2+) mobilization is mediated by the two-pore channels (TPCs). Whether NAADP acts as a messenger in astrocytes is unclear, and downstream functional consequences have yet to be defined. Here, we show that intracellular delivery of NAADP evokes Ca(2+) signals from acidic organelles in rat astrocytes and that these signals are potentiated upon overexpression of TPCs. We also show that NAADP increases acidic vesicular organelle formation and levels of the autophagic markers, LC3II and beclin-1. NAADP-mediated increases in LC3II levels were reduced in cells expressing a dominant-negative TPC2 construct. Our data provide evidence that NAADP-evoked Ca(2+) signals mediated by TPCs regulate autophagy.Fundacao do Amparo a Pesquisa do Estado de São PauloConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Biotechnology and Biological Sciences Research CouncilUniversidade Federal de São Paulo, UNIFESP, Dept Pharmacol, BR-04044020 São Paulo, BrazilUniv Roma Tor Vergata, Dept Biol, I-00133 Rome, ItalyUniversidade Federal de São Paulo, Interdisciplinary Ctr Gene Therapy, BR-09210170 São Paulo, BrazilUniv Oxford, Dept Pharmacol, Oxford OX1 2JD, EnglandUCL, Dept Cell & Dev Biol, London WC1E 6, EnglandUniversidade Federal de São Paulo, UNIFESP, Dept Pharmacol, BR-04044020 São Paulo, BrazilUniversidade Federal de São Paulo, Interdisciplinary Ctr Gene Therapy, BR-09210170 São Paulo, BrazilBiotechnology and Biological Sciences Research Council: BB/G013721/1Web of Scienc

A saúde da família sob as lentes da higiene mental Family health through the lens of mental hygiene

Procura instigar o debate sobre os determinantes sócio-históricos que condicionam a construção de políticas públicas de saúde mental aplicáveis ao contexto familiar brasileiro. As atuais políticas têm privilegiado a família como lugar estratégico de ações voltadas para a transformação social, com intervenção de vários atores, entre eles, psicólogos. Ao recuperar alguns pontos do ideário de higiene mental percebeu-se que esse discurso não é novidade na história da saúde brasileira. Embora os tempos, as famílias e os profissionais sejam outros, compreendeu-se que a busca de solução para a 'crise' da sociedade continua sendo atribuída ao indivíduo particular. A família, como expressão desse indivíduo, tem sido chamada para assumir responsabilidades que levem a sociedade na direção da 'ordem' e do 'progresso' da nação.<br>The article is meant to stimulate debate about the social and historical determinants that shape the construction of public mental health policy within the context of the Brazilian family. Current policies have emphasized the family as a strategic target of initiatives aimed at social transformation, with the intervention of different actors, including psychologists. An examination of some ideas from the field of mental hygiene suggests that this discourse is nothing new in the history of Brazilian health. While today's times, families, and professionals are different, the search for a solution to the so-called crisis of society still focuses on the individual. The family, as the expression of this individual, has been called upon to assume responsibilities that push society towards 'order' and 'progress' for the Nation