Titre du document / Document title

Exposure to octylphenol increases basal testosterone formation by cultured adult rat Leydig cells

Auteur(s) / Author(s)

MURONO Eisuke P. ⁽¹⁾ ; DERK Raymond C. ⁽¹⁾ ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

⁽¹⁾ Health Effects Laboratory Division, Pathology and Physiology Research Branch, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, M/S L-2015, 1095 Willowdale Road, Morgantown, WV 26505-2888, ETATS-UNIS

Résumé / Abstract

4-Tert-octylphenol (OP) is a breakdown product of 4-tert-octylphenol ethoxylate, which is a surfactant additive widely used in the manufacture of a variety of detergents and plastic products. OP has been reported to exhibit weak estrogenic activity in many assay systems. The studies described herein examined an unusual effect of OP in increasing constitutive testosterone levels of cultured Leydig cells from young adult rats. The increase in testosterone was both dose and time sensitive, and this response was observed in medium lacking both calcium and magnesium and containing a membrane-permeable calcium chelator, suggesting that the increase in testosterone was not mediated by an increase in the permeability of extracellular calcium into cells or the redistribution/release of calcium from intracellular stores, respectively. Cellular cAMP levels also were unaffected by OP alone in cultured Leydig cells. Furthermore, initial exposure to 2110 nM OP alone for 4h did not alter the subsequent conversion of endogenous cholesterol or exogenously added 22 (R)hydroxycholesterol to testosterone, suggesting that the increase in testosterone was not due to the enhanced availability of endogenous cholesterol or an increase in cholesterol side-chain cleavage activity, respectively. The increase in testosterone also was observed in the presence of the pure estrogen antagonist, ICI 182,780, or a 5α-reductase inhibitor, suggesting that this effect of OP was not mediated through the estrogen receptor α or β pathway or by inhibition of Leydig cell testosterone metabolism, respectively. In addition, exposure of cells to comparable concentrations of two different detergents, Triton X-100 or sodium cholate, did not increase testosterone levels, suggesting that this effect of OP was not due to its potential detergent qualities. Although these studies did not identify specific mechanism(s) that increase constitutive testosterone levels by OP, they identify specific pathways that appear not to be involved. The physiological relevance of this observation is not known; nevertheless, they illustrate potential diverse actions of OP in modulating the level of androgen secreted by Leydig cells, and they emphasize that some actions of OP do not appear to be mediated through the estrogen receptor α or β pathway.

Revue / Journal Title

Journal of steroid biochemistry and molecular biology   ISSN 0960-0760 

Source / Source

2002, vol. 81, n^o2, pp. 181-189 (54 ref.)

Langue / Language

Anglais

Editeur / Publisher

Elsevier, Oxford, ROYAUME-UNI  (1990) (Revue)

Mots-clés anglais / English Keywords

Sex steroid hormone ; Testicular hormone ; Androgen ; Male genital system ; Testicle ; Vertebrata ; Mammalia ; Rodentia ; Toxicity ; Animal ; Rat ; Poison ; Endocrine disruptor ; Phenol ; Testosterone ; Leydig cell ;

Mots-clés français / French Keywords

Hormone stéroïde sexuelle ; Hormone testiculaire ; Androgène ; Appareil génital mâle ; Testicule ; Vertebrata ; Mammalia ; Rodentia ; Octylphenol ; Toxicité ; Animal ; Rat ; Toxique ; Perturbateur endocrinien ; Phénol ; Testostérone ; Cellule Leydig ;

Mots-clés espagnols / Spanish Keywords

Hormona esteroide sexual ; Hormona testicular ; Andrógeno ; Aparato genital macho ; Testículo ; Vertebrata ; Mammalia ; Rodentia ; Toxicidad ; Animal ; Rata ; Tóxico ; Disruptor endocrino ; Fenol ; Testosterona ; Célula Leydig ;

Localisation / Location

INIST-CNRS, Cote INIST : 14629, 35400010450964.0100