Parallelism and dissociation in the actions of an Aroclor 1260-based transformer fluid on testicular androgenesis and antioxidant enzymes

The mechanism by which Aroclors and other polychlorinated biphenyls (PCBs) inhibit testicular androgenesis in vivo and in vitro has not been characterized. Here we studied in adult rats the effects of intratesticular (itt), intraperitoneal (ip) and by gavage (po) administration of Pyralene, an Aroclor 1260-based transformer fluid, on testicular androgenesis and oxidative status in androgen-producing interstitial cells and liver. Pyralene markedly decreased in vitro agonist stimulated androgenesis 24 h after bilateral itt-injection (25 mug/testis), 24 h and 96 It after single ip-injection (10 and 50 mg/kg body weight), and 96 h after po-administration (7 x 10 mg and 7 x 50 mg/kg body weight daily). Inhibited androgenesis was accompanied by changes in the activity of antioxidant enzymes (AOEs) in interstitial cells after local itt-treatment and occasionally after systemic Pyralene application. Among changes in the activity, glutathione peroxidase and catalase reflected relatively well the toxicity of Pyralene in these cells. In liver, glutathione-S-transferase (GST) and glutathione peroxidase activities were enhanced after po-treatment and total glutathione (tGSH) content and lipid peroxidation (LP) were enhanced after ip-administration. These results indicate that Pyralene inhibits androgenesis independently of the method of its administration. The results also suggest that changes in the oxidative status in testicular milieu are not critical for Pyralene-induced inhibition of androgenesis. (C) 2003 Elsevier Ireland Ltd. All rights reserved.