Effects of human insulin-like growth factor-I on release of growth hormone by rainbow trout (Oncorhynchus mykiss) pituitary cells.
A recombinant human IGF-I (rhIGF-I) was applied to primary cultures of rainbow trout pituitary cells. In wells containing 3 x 10(4) and 6 x 10(4) cells/well, rhIGF-I inhibited basal GH release both in short (6 h) and long (12 and 24 h) exposures. The decline in GH release was dose-dependent over the range of 0.01 and 100 mM. The combination of rhIGF-I and low concentrations of synthetic somatostatin (SRIF) enhanced the inhibitory effect of rhIGF-I in an additive manner. Any appreciable effect of rhIGF-I on PRL release was not evidenced. To our knowledge, this report demonstrates for the first time the participation of IGFs on the inhibitory component of fish GH regulation.
Pérez-Sánchez
J
J
Inst. Acuicultura, CSIC, Castellón, Spain.
Weil
C
C
Le Bail
P Y
PY
D000818:Animals; D002478:Cells, Cultured; D005246:Feedback; D013006:Growth Hormone / Q000378:metabolism*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D011994:Recombinant Proteins / Q000494:pharmacology; D014337:Trout
D011994:Recombinant Proteins; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone