Effect of Protein Kinase C Activators on the Uptake of Gaba by Rat Brain Synaitosomes

Abstract

Synaptosomes were prepared from rat brain by a discontinuous Ficoll gradient method and used for studying the uptake of labelled GABA. Two GABA uptake components were evidenced, a high (Km = 3.13 μM) and a low (Km = 92.4 μM) affinity one. Preincubation of synaptosomes with two different activators of protein kinase C, phorbol 12, 13-diacetate (PDAc) and oleyl-acetyl glycerol (OAG), resulted in a change of GABA uptake. In particular, the low affinity component increased its v_Max by 58–74%, with no change in the Km. No statistically significant modification was detected for the high affinity component

Key Words:

• PKC
• PKC activators
• GABA uptake
• rat brain
• synaptosomes