Please use this identifier to cite or link to this item:
|Title:||Insulin-like growth factor-I inhibits rat arterial K-ATP channels through PI 3-kinase.|
Willars, Gary B.
Standen, N. B.
Davies, N. W.
|Citation:||Biochemical and Biophysical Research Communications, 2008, 374 (4), pp. 742-746.|
|Abstract:||Since, in addition to its growth-promoting actions, insulin-like growth factor-I (IGF-I) has rapid vasoactive actions, we investigated the effects of IGF-I on whole-cell ATP-sensitive K+ (K-ATP) currents of rat mesenteric arterial smooth muscle cells. IGF-I (10 or 30 nM) reduced K-ATP currents activated by pinacidil or a membrane permeant cAMP analogue. Inhibition of phospholipase C, protein kinase C, protein kinase A, mitogen-activated protein kinase or mammalian target of rapamycin (mTOR) did not prevent the action of IGF-I. However, inhibition of K-ATP currents by IGF-I was abolished by the tyrosine kinase inhibitor genistein or the phosphoinositide 3-kinase inhibitors, LY 294002 and wortmannin. Intracellular application of either phosphatidylinositol 4,5-bisphosphate (PIP-2) or phosphatidylinositol 3,4,5-trisphosphate (PIP-3) increased the K-ATP current activated by pinacidil and abolished the inhibitory effect of IGF-I. Thus, we show regulation of arterial K-ATP channels by polyphosphoinositides and report for the first time that IGF-I inhibits these channels via a phosphoinositide 3-kinase-dependent pathway.|
|Rights:||This is the author's final draft of the paper published as Biochemical and Biophysical Research Communications, 2008, 374 (4), pp. 742-746. The final version is available from http://www.sciencedirect.com/. Doi: 10.1016/j.bbrc.2008.07.100|
|Appears in Collections:||Published Articles, Dept. of Cell Physiology and Pharmacology|
Items in LRA are protected by copyright, with all rights reserved, unless otherwise indicated.