Glutamate release is involved in PAF-increased cyclic GMP levels in hippocampus

The involvement of glutamate in PAF-increased cyclic GMP levels was studied . Glutamate treatment caused a dose-response increase of cyclic GMP levels in hippocampal slices. The presence of 1 mM glutamate did not modify the ef fect caused by 10(-7) M PAF. To elucidate the involvement of glutamate in t his action, slices were treated with PAF in the presence of MK-801, a NMDA receptor antagonist. Results indicate that PAF-increased cyclic GMP levels were obtained by NMDA receptors activation. Finally, results obtained from the experiments performed with PAF in the presence of riluzole, to inhibit the glutamate release, demonstrated that glutamate release is a stage in th e PAF-induced increase of cyclic GMP levels in hippocampus.