NEUROCHEMICAL PROFILE OF THE DORSAL HIPPO CAMPUS AND ANTIAVERSIVE EFFECTS OF ANXIOLYTICS AT DIFFERENT ANXIETY MODELS IN RATS

Chemical stimulation of the dorsal hippocampus by serotonin and GABA d ecreases anxiety in a test of avoidance of precarious situation but no t of illuminated platform. Intrahippocampal injection of chlordiazepox ide induced similar effect. Microinjection of glutamic acid into the h ipppcampus increases and that of dopamine decreases anxiety in the tes t of avoidance of illuminated platform but not of precarious situation . Ipsapiron locally injected unto the dorsal hippocampus induces antia versive effect counteracting anxiety states in both behavioural models . A conclusion is drown that hippocampal monoanin- and acidergic mecha nisms are functuinally different in anxiety of different modes of aver sive origin. Differences in spectra of anxiolytic action of chlordiaze poxide and ipsapiron may be underlied by nonsimilar degree of involvem ent of these transmitter mechanisms in anxiety states being formed by aversive influences of different biological significance.