Biomaterial Database

RMI 12,936 and pseudopregnancy in rats. 1979

R Salmonsen, and I F Lau, and S K Saksena

RMI 12,936, when injected subcutaneously at a dose of 2 mg, either on Day 6 of psuedopregnancy (PSP-6) or on PSP-6,7 and 8, shortened the duration of PSP from 12.3 +/- 0.3 (control) to 8.3 +/- 0.1 or 8.7 +/- 0.2 days, respectively. During PSP, plasma progesterone (delta 4P) levels in the peripheral plasma showed a trend of decrease by PSP-9 (52.0 +/- 4.6 on PSP-8 to 42.3 +/- 3.1 ng/ml on PSP-9). Administration of RMI 12,936 on PSP-6 resulted in a significant decrease in delta 4P and pregnenolone (delta 5P) within 24 hr after treatment but caused no apparent changes in 20 alpha-dihydroprogesterone (20 alpha-DHP) levels. However, a significant decrease of delta 4P/20 alpha DHP ratio was encountered 24 hr after RMI 12,936 treatment. The persistent occurrence of proestrous smear after PSP termination, but absence of estrous vaginal cytology, might be attributed to the slight estrogenicity of RMI 12,936. After the premature termination of pseudopregnancy induced by RMI 12,936, the female rats were sexually receptive for at least 3 weeks but failed to conceive, suggesting that this compound has a prolonged contraceptive effect.

UI	MeSH Term	Description	Entries
D011284	Pregnenolone	A 21-carbon steroid, derived from CHOLESTEROL and found in steroid hormone-producing tissues. Pregnenolone is the precursor to GONADAL STEROID HORMONES and the adrenal CORTICOSTEROIDS.	5-Pregnen-3-beta-ol-20-one,5 Pregnen 3 beta ol 20 one
D011374	Progesterone	The major progestational steroid that is secreted primarily by the CORPUS LUTEUM and the PLACENTA. Progesterone acts on the UTERUS, the MAMMARY GLANDS and the BRAIN. It is required in EMBRYO IMPLANTATION; PREGNANCY maintenance, and the development of mammary tissue for MILK production. Progesterone, converted from PREGNENOLONE, also serves as an intermediate in the biosynthesis of GONADAL STEROID HORMONES and adrenal CORTICOSTEROIDS.	Pregnenedione,Progesterone, (13 alpha,17 alpha)-(+-)-Isomer,Progesterone, (17 alpha)-Isomer,Progesterone, (9 beta,10 alpha)-Isomer
D011555	Pseudopregnancy	An acyclic state that resembles PREGNANCY in that there is no ovarian cycle, ESTROUS CYCLE, or MENSTRUAL CYCLE. Unlike pregnancy, there is no EMBRYO IMPLANTATION. Pseudopregnancy can be experimentally induced to form DECIDUOMA in the UTERUS.	Pseudocyesis,Pseudopregnancies
D005260	Female		Females
D000737	Androstenols	Unsaturated androstanes which are substituted with one or more hydroxyl groups in any position in the ring system.	Hydroxyandrostenes
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D045165	Testosterone Congeners	Steroidal compounds related to TESTOSTERONE, the major mammalian male sex hormone. Testosterone congeners include important testosterone precursors in the biosynthetic pathways, metabolites, derivatives, and synthetic steroids with androgenic activities.	Synthetic Androgen,Androgen Analogs,Androgen Analogues,Androgens, Synthetic,Synthetic Androgens,Analogs, Androgen,Analogues, Androgen,Androgen, Synthetic
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus