Distribution of cytoplasmic phospholipase A2 in the normal rat brain

The calcium-dependent cytoplasmic PLA2 (cPLA2) is an 85-kDa cytosolic enzyme that has been detected in cytosolic fractions from rat brain. With immunocytochemical methods, this cPLA2 is distributed throughout rat brain. Very dense immunostaining is observed in the superior olivary nucleus, periolivary nucleus, facial motor nucleus and dorsal cochlear nucleus in hindbrain whereas light immunostaining is seen in forebrain and midbrain areas. Assays of cPLA2 activity in forebrain, midbrain and hindbrain show the highest specific activity in the hindbrain. The distribution of cPLA2 coincides with that of protein kinase C activity in rat brain. The presence of cPLA2 and PKC in hindbrain suggests that these enzymes play a central role in neurotransmitter release, long-term potentiation and neuritogenesis in this area under normal conditions.