ABSTRACT
Objective To ob se rve the effects of danazol on hypothalamus-pituitary-gonad axises and expressi ons of hypothalamic GnRH and pituitary GnRH receptor mRNA in female rats. Methods Female rats at 5 days of age were given a sin gle subcutaneous injection of 300 ?g danazol to induce true precocious puberty. Animals were divided into 3 groups: normal control, model group and vehicle gro up. The day of vaginal opening from 25 days of age was monitored, and the establ ishment of first estrus cycle from the day of vaginal opening was investigated b y examination of vaginal smears. The weights of body, pituitary, adrenal, uterus and ovary were measured to identify the developmental status of main organs. Th e expressions of hypothalamic GnRH and pituitary GnRH receptor mRNA were assayed by semi-quantitative RT-PCR. Results Female rats treated with danazol significantly (P