title: Changes in oviductal VIP content induced by sex steroids and inhibitory effect of VIP on spontaneous oviductal contractility.
abstract: The content of vasoactive intestinal polypeptide (VIP) in rabbit oviducts was determined using a radioimmunoassay technique. Treatment with oestrogen (polyestradiolphosphate) alone for 5 days caused a significant increase in oviductal VIP content, whereas addition of progesterone during the last 3 days of an 8 day polyestradiol-phosphate treatment resulted in a return of VIP content to control levels. The effect of VIP on oviductal smooth muscle contractility was investigated using an in vitro system. It was found that VIP caused a reduction of spontaneous contractile activity in doses as low as 10(-10) M and this reduction in motor activity was strictly dose dependent with an ED50 value similar to that reported for the VIP activity on rabbit myometrial smooth musculature.
mesh_terms: D000818:Animals; D004958:Estradiol / Q000031:analogs & derivatives* / Q000494:pharmacology; D005187:Fallopian Tubes / Q000378:metabolism*; D005260:Female; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects; D011374:Progesterone / Q000494:pharmacology*; D011817:Rabbits; D011863:Radioimmunoassay; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D014660:Vasoactive Intestinal Peptide; D011374:Progesterone; D004958:Estradiol; C008958:polyestradiol phosphate