Effects of 2,5-dimethylpyrazine on reproductive and accessory reproductive organs in female rats.

The effects of 2,5-dimethylpyrazine on reproductive and accessory reproductive organs in female rats were studied. Following the administration of 2,5-dimethylpyrazine, uterus weight was significantly decreased while ovary weight was not affected, nor was there any influence on serum level of estradiol. The increase of uterine weight observed following estradiol injection after ovariectomy was inhibited by 2,5-dimethylpyrazine pretreatment. The uptake of 3H-estradiol into the uterus was also significantly decreased by 2,5-dimethylpyrazine. On the other hand, chlorpromazine administration resulted in significant decrease in ovary and uterus weight as well as serum estradiol level. These results suggest that 2,5-dimethylpyrazine may have direct inhibitory action on the uterus of rats.