[Suppression by luteectomy of the simultaneous increase in intramammary pressure and blood oxytocin levels induced by the injection of PGF2-alpha in ewes].
Seven lactating Lacaune ewes underwent either a total luteectomy on day 19 of pregnancy (D19) (compensated from that stage by a daily progesterone supplementation of 25 mg to ensure embryonic survival; group 1:4 animals) or a control laparotomy (group 2: 3 animals). Intra-jugular injection of 200 micrograms of a synthetic PGF2 alpha analogue (Dinolytic, Upjohn) caused an increase in the intramammary pressure (IMP) and a concomitant rise in oxytocinaemia only in the presence of a corpus luteum, ie in all ewes of groups 1 and 2 before D19 and only in those of group 2 after that stage. These experiments confirm that the corpus luteum, and not the other ovarian compartments, releases oxytocin when prostaglandin F2 alpha is administered.
Labussière
J
J
Laboratoire de la traite, INRA, Rennes, France.
Lacroix
M C
MC
Combaud
J F
JF
de la Chevalerie
F A
FA
Thomas
P
P
D000818:Animals; D003338:Corpus Luteum / Q000187:drug effects / Q000502:physiology* / Q000601:surgery; D015237:Dinoprost / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D007275:Injections, Intravenous; D007601:Jugular Veins; D008321:Mammary Glands, Animal / Q000187:drug effects / Q000502:physiology*; D010121:Oxytocin / Q000097:blood* / Q000378:metabolism; D011247:Pregnancy; D011312:Pressure; D011374:Progesterone / Q000097:blood; D012636:Secretory Rate / Q000187:drug effects; D012756:Sheep / Q000502:physiology
D011374:Progesterone; D010121:Oxytocin; D015237:Dinoprost
Suppression par la lutectomie de l'accroissement simultané de la pression intramammaire et de l'ocytocinémie, induit par l'injection de PGF2 alpha chez la brebis.