Neurotensin effects on calcium/calmodulin-dependent protein phosphorylation in rat neostriatal slices

Neurotensin (NT) is an endogenous brain tridecapeptide for which high affinity binding sites exist in the central nervous system. We have investigated the effects of NT incubation with rat neostriatal slices on calcium/calmodulin (Ca/CaM)-dependent protein phosphorylation. Slices were incubated with NT (5 or 50 nM) for 3, 10, 16 or 30 min followed by in vitro phosphorylation, electrophoresis and autoradiography. NT significantly altered the phosphorylation of a 62 kDa protein which is likely the beta subunit of the Ca/CaM dependent protein kinase. These changes may reflect the ability of NT to influence calcium mediated signal transduction.