Reference

Fourteen-day versus twenty-one-day regimens of intermittent intranasal luteinizing hormone-releasing hormone agonist combined with an oral progestogen as antiovulatory contraceptive approach

Fourteen-day versus twenty-one-day regimens of intermittent intranasal luteinizing hormone-releasing hormone agonist combined with an oral progestogen as antiovulatory contraceptive approach. Lemay, Andre; Faure, Nacia (St. Francois d'Assise Hosp., Laval Univ., Quebec, PQ G1L 3L5, Can.). J. Clin. Endocrinol. Metab., 63(6), 1379-85 (English) 1986. CODEN: JCEMAZ. ISSN: 0021-972X. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) The effects of discontinuous administration of the LH-RH agonist buserelin [57982-77-1] on pituitary-ovarian function were examd. in normal women. Buserelin (200 mg/12 h or 400 mg/24 h) was given intranasally for 4 consecutive cycles for 14 or 21 days in normally cycling women. Medroxyprogesterone acetate [71-58-9] (5 mg) was given orally twice daily from days 15-21. There was a 7-day pause between each medication cycle. Blood samples were drawn every other day for RIA of LH [9002-67-9], FSH [9002-68-0], estradiol (E2) [50-28-2], and progesterone (P) [57-83-0]. Serum FSH increased for only a few days at the beginning of each cycle, whereas sustained elevation of serum LH occurred during LH-RH agonist administration. Serum E2 increased rapidly and remained elevated during the administration of buserelin. 57-83-0 and 57982-77-1 are cas registry numbers of chemicals which are used as reagents here. Serum P remained in the follicular phase range or increased briefly after the initiation of buserelin occasionally in the 14-day regimens. After discontinuation of buserelin, E2 fell rapidly, and uterine withdrawal bleeding occurred. During the pause, FSH increased progressively. The patterns of gonadotropin response to buserelin were similar in the 6 cycles. Based on measurement of the areas of the response curves, serum LH and E2 levels were higher during the administration of 200 mg/12 h compared to 400 mg/24 h buserelin. However, down-regulation of the pituitary-ovarian axis, as evaluated by the acute gonadotropin response to buserelin on day 14, was more pronounced with 200 mg/12 h than with 400 mg/24 h. Breakthrough bleeding occurred during the pause in the 21-day schedules. The immediate cycles following buserelin administration were normal ovulatory cycles. Intermittent LH-RH agonist administration for 21 days avoided const. down-regulation of the pituitary-ovarian axis and allowed regular uterine bleeding. Combined with an appropriate P complement, it could be a useful contraceptive approach. .

Medroxyprogesterone acetate inhibits growth of hormone-dependent mammary carcinoma cells: involvement of the progesterone receptor

Medroxyprogesterone acetate inhibits growth of hormone-dependent mammary carcinoma cells: involvement of the progesterone receptor. Costa, S.Some chemicals with cas registry numbers like 34184-77-5 and 145-13-1 are also used. D.; Luengo, E.; Eppenberger, U. (Dep. Res., Univ. Clin. Med. Sch., Basel CH-4031, Switz.). Contrib. Oncol., 23(Endocr. Ther. Breast Cancer), 79-88 (English) 1986. CODEN: COONEV. DOCUMENT TYPE: Journal CA Section: 2 (Mammalian Hormones) Medroxyprogesterone acetate [71-58-9] (10-11-10-5M) inhibited the growth of the estrogen and(or) progesterone [57-83-0] receptor-pos. mammary carcinoma cell lines (MCF-7, T-47-D, and ZR-75) but did not influence the proliferation of receptor neg. cell lines (MDA-MB-231, HBL-100, and BT-20). Medroxyprogesterone acetate displaced progesterone receptor-bound 3H-labeled R 5020 [34184-77-5] with the same affinity as unlabeled R 5020 did in all 3 receptor-pos. cell lines. The presence of progesterone receptors is apparently required for medroxyprogesterone acetate-induced mammary carcinoma growth inhibition. .