Effect of ageing on Ca2+ uptake via NMDA receptors into barrel cortex slices of spontaneously hypertensive rats.

ABSTRACT

In the normal ageing cortex of the brain there is a group of dying neurons with shrinking dendritic trees and a group of surviving neurons with expanding dendritic trees. The ageing process affects neurotransmitter systems, including glutamate neurons and NMDA receptors. Calcium is an important signaling molecule. It enters brain cells through NMDA receptors and voltage-gated calcium channels. Since NMDA receptors play an important role in brain plasticity, calcium uptake through NMDA receptors can be used as a measure of brain activity. This study therefore sought to determine the effect of ageing on NMDA-stimulated Ca(2+) uptake into barrel cortex slices of Spontaneously Hypertensive Rats (SHR) compared to control Wistar-Kyoto rats (WKY). Young rats (prepuberty, 4-6 weeks) and adult rats (14-16 weeks) were used in the study. The results show a significant decrease in NMDA-stimulated Ca(2+) uptake in adult rats compared to their young litter-mates. It can be concluded that ageing negatively affects NMDA-stimulated Ca(2+) uptake into barrel cortex slices of SHR and WKY.