[Effects of fenvalerate on reproductive and endocrine systems of male rats].
OBJECTIVE
To evaluate the impairment of fenvalerate on reproductive and endocrine systems and clarify the mechanism of action.


METHODS
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).


RESULTS
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).


CONCLUSIONS
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.
Hu
Jing-Yi
JY
Key Laboratory of Jiangsu Province Applied Toxicology, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
Wang
Shou-Lin
SL
Zhao
Ren-Cheng
RC
Yang
Jun
J
Chen
Jing-Heng
JH
Song
Ling
L
Wang
Xin-Ru
XR
D000818:Animals; D004703:Endocrine System / Q000187:drug effects* / Q000378:metabolism; D005640:Follicle Stimulating Hormone / Q000097:blood; D007306:Insecticides / Q000633:toxicity; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009570:Nitriles; D011722:Pyrethrins / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012098:Reproduction / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects; D013739:Testosterone / Q000097:blood
D007306:Insecticides; D009570:Nitriles; D011722:Pyrethrins; D013739:Testosterone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C017690:fenvalerate