CHANGES IN INTERLEUKIN-1 PRODUCTION OF PERITONEAL-MACROPHAGES DURING ESTROUS-CYCLE IN GOLDEN-HAMSTERS

The present study demonstrated the change in interleukin-1 (IL-1) prod uction of peritoneal macrophages during the estrous cycle in golden ha msters and discussed its possible roles in ovarian function. Macrophag es were collected from the peritoneal cavity at 0900 h on various days of the estrous cycle and incubated for 6 h in the presence of ovine p ituitary LH (500 ng/ml). The IL-I concentration in the media was measu red by bioassay with the A375S2 human melanoma cell line. The number o f macrophages significantly (P<0.01) increased on estrus and proestrus compared with diestrus 1 or diestrus 2. LH-induced production of IL-1 was also greater (P<0.01) on proestrus (292 +/- 36 pg/10(6) cells/ml) and estrus (222 +/- 30 pg/10(6) cells/ml) than on diestrus 1 (34 +/- 15 pg/10(6) cells/ml) or diestrus 2 (117 +/- 16 pg/10(6) cells/ml). To clarify the factor inducing the changes in peritoneal macrophages, ha msters were ovariectomized on diestrus 1, and 3 weeks later the animal s were treated with sc injections of progesterone (200 mu g/day), test osterone (100 mu g/day), estradiol (10 mu g/day) or sesame oil for thr ee days. The hamsters were killed 24 h after the last injection, and t he number and IL-I producing capacity of macrophages were determined. The number of macrophages and their response to LH to produce IL-I wer e increased significantly (P<0.01) by estradiol treatment but not by p rogesterone or testosterone treatment. It was concluded that the perit oneal macrophages became more sensitive to LH to produce IL-1 on proes trus and estrus in cyclic hamsters, and that these changes in macropha ges, probably induced by estradiol, would play important roles in ovar ian function.