Joint action of phoxim and fenvalerate on spermatogenesis of male rats / 中华男科学杂志

<p><b>OBJECTIVE</b>To assess the joint toxicity of phoxim (Pho) and fenvalerate (Fen) on the spermatogenesis of male rats and to clarify its mechanism.</p><p><b>METHODS</b>Based on the three administrative levels of factorial analysis (3 x 3) of Pho and Fen, i. e. their half lethal dose (LD50) 1/250 LD50 (5.9, 2.4 mg/kg) and 1/50 LD50 (29.4, 12.0 mg/kg) and the control, 135 adult male SD rats were randomly assigned to9 groups, the control (0.0 mg/kg), Pho (5.9, 29.4 mg/kg), Fen (2.4, 12.0 mg/kg), Pho + Fen (5.9 + 2.4, 5.9 + 12.0, 29.4 + 2.4, 29.4 + 12.0 mg/kg), and treated intragastrically with different doses of Pho, Fen and Pho + Fen for 15 and 30 days. The levels of serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T) and testis homogenate T were determined by radioimmunoassay (RIA), the activity of testicular marker enzymes such as acid phosphatases (ACP) and gamma-glutamyl transpeptidase (gamma-GT) examined, and the sperm head count measured for the changes of daily sperm production (Spr).</p><p><b>RESULTS</b>At 15 days, obvious interaction was observed between Pho and Fen in both serum LH and FSH (P < 0.05), as well as between their reproductive toxicities. With the increase in doses, the joint action was synergistic in LH (P < 0.05) and antagonistic in FSH (P < 0.01) at a high dose ( 29.4 + 12.0 mg/kg). At 30 days, marked interaction between Pho and Fen was noted in the content of homogenate T (P < 0.05) , with a joint synergistic effect. At 15 and 30 days, with the increase of doses, both Pho and Fen reduced Spr and the activity of ACP and gamma-GT, but Pho + Fen showed no obvious interaction in them (P > 0.05) , and their joint action was an additive effect.</p><p><b>CONCLUSION</b>Pho and Fen jointly impaired spermatogenesis in a dose- and time-dependent manner. Their joint action exhibited mainly as a synergistic effect, an additive effect and increased toxicity.</p>

Effects of fenvalerate on reproductive and endocrine systems of male rats / 中华男科学杂志

<p><b>OBJECTIVES</b>To evaluate the impairment of fenvalerate on reproductive and endocrine systems and clarify the mechanism of action.</p><p><b>METHODS</b>Different doses of fenvalerate (0, 2, 4, 12, 60 mg/kg) were orally treated to the adult male SD rats for 15 days and 30 days, respectively. The levels of serum follicle stimulating hormone(FSH), luteinizing hormone (LH), testosterone(T) and testis homogenate T were determined by radioimmunoassay(RIA). Besides, the activity of testicular marked enzymes such as acid phosphatases(ACP) and gamma-glutamyl transpeptidase(gamma-GT) were examined, and sperm head counts were measured to explain the changes of daily sperm production(Spr).</p><p><b>RESULTS</b>In fifteen days, serum FSH levels markedly increased in rats exposed to fenvalerate of < or = 12 mg/kg groups(P < 0.01) and serum levels of LH increased in 12 mg/kg group(P < 0.01). In addition, T levels in testis homogenates decreased after treated with the doses of > or = 12 mg/kg groups compared with the control group(P < 0.01). In thirty days, serum contents of FSH were significantly elevated in the doses of > or = 12 mg/kg groups(P < 0.01) and homogenate levels of T were diminished in the low dose group(2.4 mg/kg) (P < 0.05). Activity of ACP increased in 12 mg/kg group after fifteen days(P < 0.05) and was restrained in the high dose group(60 mg/kg) in thirty days(P < 0.05), but the contents of gamma-GT were arrested with different doses dependently in the testis(P < 0.05). Fenvalerate caused dose-dependent reduction in sperm head counts and daily sperm production, which markedly reduced at the doses of > or = 12 mg/kg groups(P < 0.01).</p><p><b>CONCLUSIONS</b>Fenvalerate has obvious reproductive toxicity on male rats and can change their serum and testis homogenate levels of sex hormone or activity of testicular marked enzymes, which may be correlated with the impairment of Sertoli cell and spermatogenic epithelium.</p>