Effects Of Exposure To Toluene On The Gonadotropic Hormone In The Female Rats

Objective:To investigate to the effects of a subchronic exposure to toluene on estrous cyclicity,GTH and LH,FSH in the blood serum.Our study would provide a futher scientific basis for reproductive endocrine toxicity of toluene.Methods:Beginning at 60 days of age,only females displaying 4 or 5 days estrous cycles were included in the experimental groups.40 females were randomly divided into 4 groups and they were respectively gavaged with 0,35,70,330mg/kg toluene for 40 to 45 days.We examined the effects of toluene exposure on estrous cyclicity,At 40 to45 days,choosing rats which were in estrus and collecting tail vein blood to measure LH content and FSH content in the blood serum. Meanwhile we extract the appendices suprasphenoidalis and measure immunoreactive substance in the respective appendices suprasphenoidalis.Results:1.There was not a significant difference in the mean number of regular cycles,the days of proestrus,estrus and dioestrus during the 40-day period in the 35,70 mg/kg toluene groups compared to the controls(P＞0.05).Between 330mg/kg toluene and controls,there was a significant difference in the mean number of days in estrus(P=0.001),the regular cycles(P＜0.001) and the rate of abnormal cycles(P＜0.05).2.The LH contents and the FSH contents of high dos team and the middle dos team were significantly higher than the control team(P＜0.05).the low dos team didn't reach statistically significance compared to the control(P＞0.05). 3.The immunoreactive substance of GTH in the high dos team and the middle dos team were significantly higher than the control team(P＜0.05).the low dos team didn't reach statistically significance compared to the control(P＞0.05).Conclusion:1.Toluene made estrous cycles irregular which mainly manifested in persistent estrus.The possible reasonwas that toluene supressed preovulatory LH surge and made ovulation inhibit or delay.2.toluene could accrescence the LH contents and the FSH contents of the blood serum, Meanwhile could accrescence the immunoreactive substance of GTH.