[In vitro production of prostaglandins by the uterine and ovarian tissues of pseudopregnant rabbits in luteolysis and mechanism of luteolysis induced by PGF2 alpha (author's transl)].
Six hours' incubation with the uterine and ovarian tissues of pseudopregnant rabbits was carried out to compare their abilities to produce prostaglandins (PGs) at the various stages of pseudopregnancy. In the endometrial tissue, significant increase in PGF production was observed near luteolysis (p less than 0.001). 6-Keto PGF1 alpha production by the myometrium was also shown to increase on mid and late phase (p less than 0.01). PGE production increased slightly, but no significant difference was found. The corpus luteum and the remaining ovarian tissue were shown to have the low activity of PGF production at any stages of pseudopregnancy. 6-Keto PGF1 alpha production by the remaining ovarian tissue was significantly higher than by the corpus luteum (p less than 0.02). The results strongly suggest that the endometrium is the main site of PGF2 alpha production causing luteolysis in the pseudopregnant rabbit. In order to investigate the mechanism of luteolysis induced by PGF2 alpha, the PGF2 alpha receptor in the corpus luteum of the pseudopregnant rabbit was characterized. PGF2 alpha binding to the corpus luteum was demonstrated to be specific. Scatchard analysis of PGF2 alpha specific binding in the 16th day corpus luteum revealed the existence of two population of receptors.
D000818:Animals; D015237:Dinoprost; D004717:Endometrium / Q000378:metabolism; D005260:Female; D066298:In Vitro Techniques; D003341:Luteolysis / Q000187:drug effects; D010053:Ovary / Q000378:metabolism*; D011453:Prostaglandins / Q000096:biosynthesis*; D011460:Prostaglandins F / Q000096:biosynthesis / Q000502:physiology; D011555:Pseudopregnancy / Q000378:metabolism*; D011817:Rabbits; D011982:Receptors, Prostaglandin / Q000032:analysis; D014599:Uterus / Q000378:metabolism*
D011453:Prostaglandins; D011460:Prostaglandins F; D011982:Receptors, Prostaglandin; D015237:Dinoprost