Biomaterial Database

Comparative binding affinity study of progestins to the cytosol progestin receptor of endometrium in different mammals. 1998

K Jewgenow, and H H Meyer

Institut für Zoo- und Wildtierforschung im Forschungsverbund Berlin, Germany.

The relative binding affinity of 5 alpha-reduced progestins and a newly synthesized antiprogestin J912 (progesterone 100%) was determined in a competitive receptor binding assay using [3H]ORG-2058 as radiolabeled ligand for the progestin receptor. Uteri obtained from 12 different species of four mammalian orders were examined. The relative binding affinity of 75-100% and a blood prevalence of 5 alpha-pregnane-3,20-dione in horses and African elephants suggest a biological role of this particular 5 alpha-reduced progesterone. For pigs the binding affinity of 5 alpha-pregnane-3,20-dione was about 50% of progesterone, but blood levels are unknown. In all other cases the low binding affinity of investigated progestins precludes possible biological role. For 5 alpha-pregnane-3 alpha-ol-20-one, 5 alpha-pregnane-20 alpha-ol-3-one, and 5 alpha-pregnane-3 beta,20 alpha-diol the relative binding affinity was less than 1%. A rather low binding (< 15%) was observed in 5 alpha-pregnane-3,20-dione in all ruminant species investigated. The antiprogestin J912 was found to be highly efficient in displacing progesterone from its endometrial binding sites in carnivores and might therefore be used for pregnancy interruption during diapause in certain species, e.g., in captive bears.

UI	MeSH Term	Description	Entries
D007120	Immunochemistry	Field of chemistry that pertains to immunological phenomena and the study of chemical reactions related to antigen stimulation of tissues. It includes physicochemical interactions between antigens and antibodies.
D010527	Perissodactyla	An order of ungulates having an odd number of toes, including the horse, tapir, and rhinoceros. (Dorland, 27th ed)	Perissodactylas
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011372	Progestins	Compounds that interact with PROGESTERONE RECEPTORS in target tissues to bring about the effects similar to those of PROGESTERONE. Primary actions of progestins, including natural and synthetic steroids, are on the UTERUS and the MAMMARY GLAND in preparation for and in maintenance of PREGNANCY.	Gestagenic Agent,Progestagen,Progestagenic Agent,Progestational Agent,Progestational Compound,Progestational Hormone,Progestogen,Progestogens,Gestagen,Gestagen Effect,Gestagen Effects,Gestagenic Agents,Gestagenic Effect,Gestagenic Effects,Gestagens,Progestagenic Agents,Progestagens,Progestational Agents,Progestational Compounds,Progestational Hormones,Progestin,Progestin Effect,Progestin Effects,Progestogen Effect,Progestogen Effects,Agent, Gestagenic,Agent, Progestagenic,Agent, Progestational,Compound, Progestational,Effect, Gestagen,Effect, Gestagenic,Effect, Progestin,Effect, Progestogen,Effects, Gestagen,Effects, Gestagenic,Effects, Progestin,Effects, Progestogen,Hormone, Progestational
D011980	Receptors, Progesterone	Specific proteins found in or on cells of progesterone target tissues that specifically combine with progesterone. The cytosol progesterone-receptor complex then associates with the nucleic acids to initiate protein synthesis. There are two kinds of progesterone receptors, A and B. Both are induced by estrogen and have short half-lives.	Progesterone Receptors,Progestin Receptor,Progestin Receptors,Receptor, Progesterone,Receptors, Progestin,Progesterone Receptor,Receptor, Progestin
D002335	Carnivora	An order of MAMMALS, usually flesh eaters with appropriate dentition. Suborders include the terrestrial carnivores Fissipedia, and the aquatic carnivores CANIFORMIA.
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D004606	Elephants	Large mammals in the family Elephantidae, with columnar limbs, bulky bodies, and elongated snouts. They are the only surviving members of the PROBOSCIDEA MAMMALS.	African Elephants,Asiatic Elephants,Elephas maximus,Loxodonta,African Elephant,Asiatic Elephant,Elephant,Elephant, African,Elephant, Asiatic,Elephants, African,Elephants, Asiatic
D004717	Endometrium	The mucous membrane lining of the uterine cavity that is hormonally responsive during the MENSTRUAL CYCLE and PREGNANCY. The endometrium undergoes cyclic changes that characterize MENSTRUATION. After successful FERTILIZATION, it serves to sustain the developing embryo.	Endometria
D005260	Female		Females