Characteristics of the norepinephrine-stimulated phosphatidylinositol turnover in rat pineal cell dispersions

Publisher Website
Google Scholar
Abstract
Dispersed rat pineal cells can be used for the study of the phosphatidylinositol effect. The response to (−)-norepinephrine of the incorporation of32Pi into phospholipids is linear with time and cell concentration, stereospecific, and mediated through α1-adrenergic receptors. Na+ in the incubation medium is obligatory for labeling of phosphatidylinositol and phosphatidylcholine by32P. In the absence of K+ incorporation of32P is drastically lowered and no stimulation by norepinephrine occurs. Rb+ can replace K+. Omission of Ca2+ or substitution with Sr2+ preferentially lowers incorporation of radioactivity into phosphatidylcholine. Mg2+ is not required for basal or stimulated labeling.