Prostaglandin F2 alpha-induced release of oxytocin from ovine corpora lutea in vitro.
Prostaglandin (PG)F2 alpha, in the dose range 1-10(4) nM, failed to elicit oxytocin secretion in vitro from ovine luteal tissue on day 12 of the estrous cycle (estrus = Day 0), during a 60 minute period. Preincubation of luteal slices for 6 hours prior to treatment suggested that tissue desensitization due to the release of endogenous prostaglandins by tissue preparation is not responsible for this lack of response. However, in luteal tissue collected on day 6 of the ovine estrous cycle, PGF2 alpha stimulated oxytocin release in a dose-dependent manner. This apparent change in sensitivity of the ovine corpus luteum in vitro may be due to a combination of a reduction in the luteal oxytocin available for release and saturation of PGF2 alpha receptors in the more mature tissue.
Cooke
R G
RG
Department of Veterinary Preclinical Sciences, University of Liverpool, Neston, South Wirral, U.K.
Ahmad
N
N
D000818:Animals; D003338:Corpus Luteum / Q000378:metabolism*; D015237:Dinoprost / Q000494:pharmacology*; D004971:Estrus / Q000502:physiology*; D005260:Female; D066298:In Vitro Techniques; D010121:Oxytocin / Q000378:metabolism*; D012756:Sheep
D010121:Oxytocin; D015237:Dinoprost