“… CCK-8 ) to circular muscle …,5-bisphosphate ( PtdInsP2 ) (50 +/- 6%) and PtdInsP (38 +/- 9%), which reached a nadir in 15 s. Addition of CCK-8 to longitudinal muscle cells … +/- 6%); PtdInsP2 levels, which were three times lower in this cell type, did not change throughout the period of stimulation.”