Expression of Ca2+-dependent (classical) PKC mRNA isoforms after transient cerebral ischemia in gerbil hippocampus.

Cerebral ischemia is known to modify the expression of genetic information in the brain. To complement this knowledge, in the present study we have estimated the expression of calcium- and phospholipid-dependent (classical) protein kinase C (c PKC) isoform mRNAs (alpha, beta1 and gamma) at different time following ischemia. Forebrain cerebral ischemia was performed on Mongolian gerbils by 5 minutes bilateral occlusion of common carotid arteries. At the pointed time the cytoplasmic RNA was extracted from hippocampus and the expression of PKC mRNA quantified by RT PCR technique using GAPDH expression as an internal standard. Results indicate that only one gamma isoform of cPKC mRNA expression becomes significantly modified in postischemic hippocampus. A transient increase up to 145% of control within the first 3 h was followed by its decline to 60-65% at a longer recirculation period. This lowered levels returned back to control at 72 h postischemic recovery. This result indicates that gamma PKC could be particularly sensitive to ischemic insult and would react in accordance with the other early signals determining ischemic outcome.