[In utero exposure to dichlorvos induces apoptosis of Leydig cells in rats].
OBJECTIVE
To observe the influence of the organophosphate insecticide dichlorvos on the apoptosis of Leydig cells in the male offspring of the SD rats exposed to dichlorvos, and to investigate the role of the changes of Leydig cells in genitourinary malformation.


METHODS
Twenty-one pregnant SD rats were divided into a corn oil control group and 6 dichlorvos groups, the former given by gavage 1.0 ml corn oil daily, and the latter dichlorvos at the dose of 1, 4, 8, 16, 20 and 24 mg/kg daily from the 12th to 17th day of conception. After birth, 5 male neonates were randomly selected from each of the control and dichlorvos groups, and their testes were harvested to be analyzed by HE staining, immunohistochemistry with anti-caspase-3 antibodies and DAPI fluorescent staining. At 90 days after birth, another 5 of the male offspring were taken from each group and their testes were collected for the same analyses.


RESULTS
Statistically significant differences were found in the number of both the caspase-3 positive and DAPI labeled Leydig cells in the testes of the rat offspring between the corn oil and the 4, 8, 16, 20 and 24 mg/kg dichlorvos groups (P < 0.05), but not between the control and the 1 mg/kg dichlorvos groups (P > 0.05). The apoptosis of Leydig cells was increased in the male offspring of the dichlorvos-exposed SD rats in a dose-dependent manner.


CONCLUSIONS
Exposure of pregnant rats to dichlorvos can increase the apoptosis of Leydig cells in the male offspring, which, in turn, may reduce the number of Leydig cells, interfere with the testis function during the embryonic period, and damage the development of the genitourinary system.
Zeng
Li
L
Division of Pediadric Urology, Department of Pediadric Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China.
Wang
Yu-Yun
YY
Zhang
Jie
J
Lin
Ping
P
Gong
Xue-De
XD
Huang
Lu-Gang
LG
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis; D004006:Dichlorvos / Q000633:toxicity*; D005260:Female; D007985:Leydig Cells / Q000166:cytology / Q000187:drug effects*; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000166:cytology
D004006:Dichlorvos