Scherer N M, Ferguson J E
Biochem Biophys Res Commun. 1985 May 16;128(3):1064-70. doi: 10.1016/0006-291x(85)91048-4.
Regulation of many cell systems has been shown to be mediated by Inositol 1,4,5-trisphosphate which causes a release of calcium from intracellular sites. We have shown that release of Ca2+ from sarcoplasmic reticulum microsomes was not stimulated by IP3. The phorbol ester, TPA, also had no effect on Ca2+ release or Ca2+ ATPase activity. Thus, it is unlikely that the breakdown of polyphosphatidylinositides serves as a second messenger to mediate release of Ca2+ in skeletal muscle.
