Nicotinic stimulation of polyphosphoinositide turnover in rat adrenal medulla slices.

When rat adrenal medulla slices, treated with atropine (1 X 10(-6) mol X l-1], were stimulated with acetylcholine (1 X 10(-5) mol X l-1), an enhanced 32P incorporation into phosphatidylinositol-bis-phosphate (PIP2) and phosphatidylphosphate (PIP) was observed. On the ather hand, stimulation of myo-[3H] inositol prelabelled slices led to a decline in radioactivity of PIP2, indicating an increased turnover of this phospholipid. A possible affection of monoesterphosphate groups of PIP2 or of both PIP2 and PIP during cholinergic nicotinic stimulation is assumed.