Effect of gamma-hydroxybutyrate and its antagonist NCS-382 on spontaneous cell firing in the prefrontal cortex of the rat.

Gamma-hydroxybutyrate (GHB) at low doses (5-10 mg/kg i.p.) increased and at high doses (160-320 mg/kg i.p.) decreased the spontaneous firing rate of prefrontal cortex (PFC) neurons recorded in urethane-anesthetized rats. Only excitations were blocked by NCS-382, a specific GHB receptor antagonist; this suggests that the excitatory effect of low doses of GHB is mediated by a GHB receptor whereas the inhibitory effect of high doses of GHB involves a more complex mechanism.