Effect of somatostatin on presynaptic and postsynaptic glutamate receptors and postsynaptic GABA receptors in the neurons of rat brain.

We studied the effect of somatostatin on presinaptic NMDA receptors and postsinaptic GABA, NMDA, and AMPA receptors in rat brain. It was shown that somatostatin inhibits NMDA-induced (45)Ca(2+) uptake into synaptosomes isolated from rat brain cortex (IC50=2.8×10(-11) M). Somatostatin potentiates AMPA receptors and inhibits hippocampal NMDA receptors in the entire range of examined concentrations (10(-14)-10(-7) M); it also potentiates or inhibits GABA receptor currents in a concentration-dependent manner. Our results suggest that somatostatin modulates the function of ionotropic glutamate and GABA receptors and is involved in cognitive and neurodegenerative processes in the mammalian brain.