Decline in age-dependent, MK801-induced injury coincides with developmental switch in parvalbumin expression: cingulate and retrosplenial cortex.

Age-dependent, MK801-induced, activated caspase-3 expression in the postnatal brain is generally not observed in neurons expressing calcium-binding proteins (CaBPs), suggesting that apoptosis and calcium buffering are inversely related. In regions such as the cingulate and retrosplenial cortex, injury peaks at postnatal Day 7 (P7) and rapidly diminishes thereafter, whereas expression of calbindin (CB) and calretinin (CR) was relatively low from P0 to P7 and steadily increased from P7 to P14. At ages thereafter, CB and CR expression either remained stable then declined or rapidly declined.