Inositol-phosphate response to oxytocin stimulation in dispersed bovine mammary cells.

The effect of oxytocin on the breakdown of phosphoinositides in dispersed bovine mammary cells was studied. In the presence of 10 mM LiCl, addition of oxytocin to dispersed bovine mammary cells in which phosphatidylinositol was pre-labelled caused a time and dose-dependent increase in radioactive inositol monophosphate incorporation. These results suggested that the breakdown of phosphoinositides may be the linkage between the oxytocin receptor and contraction of mammary myoepithelial cells.