Rapid increase in inositol pentakisphosphate accumulation by nicotine in cultured adrenal chromaffin cells

When 3H]inositol-prelabeled cultured bovine adrenal chromaffin cells were stimulated with nicotine (10 microM), a large and transient increase in 3H]inositol pentakisphosphate (InsP5) accumulation was observed. The accumulation reached the maximum level at 15 s, then declined to the basal level at 2 min. Nicotine also induced 3H]inositol tetrakisphosphate (InsP4) and 3H]inositol hexakisphosphate (InsP6) accumulation with a slower time course and a lesser magnitude than 3H]InsP5. The peaks of 3H]InsP4, 3H]InsP5 and 3H]InsP6 coincided with those of 32P radioactivity, when cells were doubly labeled with 3H]inositol and inorganic 32P. These results suggest that inositol pentakisphosphate is rapidly increased by nicotine, a cholinergic agonist, in cultured adrenal chromaffin cells.