Evaluation of mutagenic/antimutagenic activity of conjugated linoleic acid in mice by micronucleus test

Conjugated linoleic acids (CLAs) are positional and geometrical isomers of linoleic acid and some researchers have shown biological activities including modulation of lipid metabolism, atherogenesis, diabetes, and immune functions. In this study, the animals were supplemented with 2% of the average feed consumption with CLA (G1 = positive control) and safflower oil (G2 = negative control) and the test groups were supplemented with CLA at the concentration of 2 and 4% of the average feed consumption. To assess the CLA potential protective effect, two groups were used; G3 = CLA 2% + cyclophosphamide (CP) and G5 = CLA 4% + CP. To assess the mutagenic effects of CLA, two groups were used; G4 = CLA 2% + NaCl 0.9% and G6 = CLA 4% + NaCl 0.9%. In order to investigate the mutagenic/antimutagenic effects of CLA, micronucleus test was used. The results showed variation of feed consumption in the groups that received 4% of CLA, when compared to the control group (G1 and G2) and CLA groups (G3 and G4) (p<0.05), during the period studied. It was observed that CLA did not show mutagenic effect at the concentrations tested (2 and 4%). Also, CLA showed antimutagenic effect at the same concentrations. However, the animals that received 4% of CLA, presented clinical signs of malnutrition.Key words: Conjugated linoleic acid, antimutagenicity, cyclophosphamide

Expression and function of G-protein-coupled receptorsin the male reproductive tract

This review focuses on the expression and function of muscarinic acetylcholine receptors (mAChRs), α1-adrenoceptors and relaxin receptors in the male reproductive tract. The localization and differential expression of mAChR and α1-adrenoceptor subtypes in specific compartments of the efferent ductules, epididymis, vas deferens, seminal vesicle and prostate of various species indicate a role for these receptors in the modulation of luminal fluid composition and smooth muscle contraction, including effects on male fertility. Furthermore, the activation of mAChRs induces transactivation of the epidermal growth factor receptor (EGFR) and the Sertoli cell proliferation. The relaxin receptors are present in the testis, RXFP1 in elongated spermatids and Sertoli cells from rat, and RXFP2 in Leydig and germ cells from rat and human, suggesting a role for these receptors in the spermatogenic process. The localization of both receptors in the apical portion of epithelial cells and smooth muscle layers of the vas deferens suggests an involvement of these receptors in the contraction and regulation of secretion.Esta revisão enfatiza a expressão e a função dos receptores muscarínicos, adrenoceptores α1 e receptores para relaxina no sistema reprodutor masculino. A expressão dos receptores muscarínicos e adrenoceptores α1 em compartimentos específicos de dúctulos eferentes, epidídimo, ductos deferentes, vesícula seminal e próstata de várias espécies indica o envolvimento destes receptores na modulação da composição do fluido luminal e na contração do músculo liso, incluindo efeitos na fertilidade masculina. Além disso, a ativação dos receptores muscarínicos leva à transativação do receptor para o fator crescimento epidermal e proliferação das células de Sertoli. Os receptores para relaxina estão presentes no testículo, RXFP1 nas espermátides alongadas e células de Sertoli de rato e RXFP2 nas células de Leydig e germinativas de ratos e humano, sugerindo o envolvimento destes receptores no processo espermatogênico. A localização de ambos os receptores na porção apical das células epiteliais e no músculo liso dos ductos deferentes de rato sugere um papel na contração e na regulação da secreção.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de FarmacologiaUNIFESP, EPM, Depto. de FarmacologiaSciEL