title: Seven-day administration of the gonadotropin-releasing hormone antagonist Cetrorelix in normal cycling women.
abstract: In contrast to gonadotropin-releasing hormone (GnRH) agonists, GnRH antagonists do not show any stimulatory effect on the pituitary but their clinical usage was precluded by severe side effects and high dose requirements. We report here on a 7-day treatment using the potent GnRH antagonist Cetrorelix ([Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]GnRH) on five women 23-33 years old. All women were ovulatory and were studied during three consecutive cycles: a control cycle, a treatment cycle and a post-treatment control cycle. Throughout the control cycles blood samples were obtained daily during cycle days 8-18 and on days 21 and 23 during the remainder of the control cycles. On the eighth day of the treatment cycle women were hospitalized at 07.00 h for 26 h. Repeated blood samples were drawn at 15-min intervals during the entire period. Subjects received 3 mg of Cetrorelix sc for the first time at 09.00 h on the eighth day of the cycle and daily at 08.00 h for the following 6 days. Blood samples were obtained daily over a period of 25 days and every third day throughout the remainder of the treatment cycle. Twenty-four hours after the first application of Cetrorelix, luteinizing hormone (LH) and estradiol were in the subnormal range and remained subnormal until the end of medication. The suppressive effect of Cetrorelix compared to pretreatment values lasted at least 6 days for LH and FSH and 11 days after the last Cetrorelix injection for estradiol.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Clinical Biochemistry, University of Bonn, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Sommer
authors.forename: K
authors.initials: K
authors.lastname: Zanger
authors.forename: T
authors.initials: T
authors.lastname: Dyong
authors.forename: C
authors.initials: C
authors.lastname: Dorn
authors.forename: J
authors.initials: J
authors.lastname: Luckhaus
authors.forename: K
authors.initials: K
authors.lastname: Diedrich
authors.forename: D
authors.initials: D
authors.lastname: Klingmüller
mesh_terms: D000328:Adult; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D006801:Humans; D007279:Injections, Subcutaneous; D007986:Luteinizing Hormone / Q000097:blood; D008597:Menstrual Cycle; D010060:Ovulation / Q000187:drug effects; D012016:Reference Values
chemical_list: D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C062876:cetrorelix