Tissue concentration, mRNA expression and stimulation of IGF-I in luteal tissue during the oestrous cycle and pregnancy of cows.
The expression of IGF-I in bovine luteal tissue was demonstrated by parallel measurement of IGF-I tissue concentration and its mRNA; highest synthesis was observed during Days 12-17 of the cycle and the first months of pregnancy. Tissue levels of IGF-I increased from Days 1-5 to Days 12-17 of the cycle followed by a rapid decrease at luteolysis; there was a continuous decline from early pregnancy until Months 6-9. Microdialysis perfusion experiments with corpora lutea in vitro at Days 8-11 of the cycle revealed a major effect: release of progesterone and oxytocin were highly stimulated in a dose-dependent manner. We suggest that IGF-I could be important in regulating the function of the bovine corpus luteum and may act in an autocrine/paracrine way.
Einspanier
R
R
Institut für Physiologie, TU München, FRG.
Miyamoto
A
A
Schams
D
D
Müller
M
M
Brem
G
G
D000818:Animals; D002417:Cattle; D003338:Corpus Luteum / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004971:Estrus / Q000378:metabolism*; D005260:Female; D007334:Insulin-Like Growth Factor I / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D009924:Organ Culture Techniques; D010121:Oxytocin / Q000096:biosynthesis; D010477:Perfusion; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D011374:Progesterone / Q000096:biosynthesis; D012333:RNA, Messenger / Q000032:analysis
D012333:RNA, Messenger; D011374:Progesterone; D010121:Oxytocin; D007334:Insulin-Like Growth Factor I