Comparison of the lytic effects of four prostaglandin analogues in the chacma baboon (Papio ursinus ursinus).

Six healthy, cycling female chacma baboons (Papio ursinus ursinus) were used to determine the luteolytic effects of four prostaglandin analogues. The compounds were administered according to a study design which made provision for adequate controls. Five to seven days following ovulation, venous blood was collected and the baboon given a single intramuscular injection of a compound at a recommended dose. Blood was then collected serially every 3 h for three samples and again at 24, 48, and 72 h to determine the continued effect of the prostaglandin analogues on corpus luteum production of progesterone. It was found that PGF2alpha-1,15-lactone, 11alpha(15S)-17-phenyl-18,19,20-trinor-ent-PGE2 methyl ester and 17-phenyl-18,19,20-trinor-PGF2alpha exhibited definite luteolytic potential in this species. Equivocal results were obtained with (15S)-15-methyl-PGF2Alpha THAM and its toxic qualities resulted in the demise of three animals.