Effect of APGW-Amide on [Ca²⁺]_i in Rat Pheochromocytoma PC12 Cells

Abstract

In order to determine whether Ala-Pro-Gly-Try-NH₂ (APGW-amide) could affect mammalian excitable cells, we investigated the effect of APGW-amide in PC12 cells. APGW-amide caused a rapid [Ca²⁺]_i elevation, which was completely prevented by elimination of extracellular Ca²⁺ with EGTA and inhibited by two L-type Ca²⁺ channel blockers. [Ca²⁺]_i elevation was also blocked by a specific PKC inhibitor and prolonged pretreatment of cells with PMA. These results indicate that APGW-amide elevates [Ca²⁺]_i in PC12 cells, possibly by Ca²⁺ influx via L-type Ca²⁺ channel activated by PKC.