Frequent occurrence of polyovular follicles in ovaries of mice exposed neonatally to diethylstilbestrol.

The occurrence of polyovular follicles (PF) was examined at 10-34 days of age in the ovaries of BALB/cCrgl female mice given five daily injections of 0.1 microgram diethylstilbestrol (DES), 2 micrograms DES, 100 micrograms progesterone (P), 137 micrograms 17 alpha-hydroxyprogesterone caproate (HPC), 20 micrograms testosterone (T), 20 micrograms 5 alpha-dihydrotestosterone (5 alpha-DHT), or oil vehicle alone starting on the day of birth, and of C57BL/Tw females given five neonatal injections of 1 microgram DES, 20 micrograms 17 beta-estradiol (E2), 50 micrograms 5 alpha-DHT, 50 micrograms 5 beta-DHT, or the vehicle alone. Ovaries of 30-day-old C57BL mice given five daily injections of 1 microgram DES starting at 3-25 days of age were also examined. PF incidence (% of PF per ovary) and PF frequency (% of mice with PF) were significantly greater in BALB/c mice receiving injections of DES, P, HPC, and T than in the controls. In DES-treated mice at 34 days, PF incidence (2-13 oocytes/follicle) was 120-340 times higher than in the controls. BALB/c mice treated with T, P, and HPC showed PF incidence (two to four oocytes/follicle) three- to six-fold higher than in the controls. In 30-day-old C57BL mice treated with T, E2, and DES, PF incidence also increased by two- to 50-fold. 5 alpha-DHT and 5 beta-DHT failed to increase PF incidence. PF incidence was significantly increased only when neonatal DES treatment was begun on days 0 to 3, but was reduced when started at days 10-25.(ABSTRACT TRUNCATED AT 250 WORDS)