Phosphorylation of MARCKS by endothelin in rat cerebral cortex slices

The action of endothelin-1 (ET-1) on protein phosphorylation was studied in rat cerebral cortex. The peptide caused an increase in P-32 incorporation into a 87 kDa protein, identified as myristoilated alanine-rich protein kin ase C substrate (MARCKS). This effect was dose- and time-dependent, and was mimicked by ET-3, sarafotoxin 6c and 12-O-tetradecanoylphorbol-13-acetate (TPA). However, it disappeared in the presence of Ro-31-8220, a protein kin ase C (PKC) inhibitor. These findings indicate that ET-1 may have a functio nal role in protein phosphorylation processes in brain.