Functional roles of the monoaminergic and aminoacidergic mechanisms of the dorsal pallidum in anxiety of different aversive origins.

Microinjections of serotonin and glutamic acid into the globus pallidus in conditions of free selection between a light and a dark chamber showed these substances to have antiaversive activity in rats in the "threatening situation" test but not in the "illuminated area" test. Local administration of dopamine and GABA into this basal ganglia formation had no effect on the mechanisms of voluntary movement but countered anxiety states in both behavioral models. These results provide evidence that the neurotransmitter systems of the dorsal pallidum have different degrees of involvement in the operative control of behavior when the modality of the aversive stimulus changes.

[Functional significance of monoamine- and aminoacidergic mechanisms of dorsal pallidum in anxiety of different aversive genesis].

Microinjections of serotonin and glutamine acid into the globus pallidus reveal antiaversive properties of these subsrances in the test with avoiding "threatening situation" but not "illuminated site" test under conditions of rats' free choice between light and dark sites. Dopamine and GABA injected locally into this formation of basal ganglia do not affect the mechanisms of voluntary movement, but counteract the conditions of anxiety in both models of behavior. The results testify to unequal involvement of neurotransmitter systems of the dorsal pallidum into operative regulation of behavior with changes of aversive stimulus modality.

Neurochemical mechanisms of the dorsal pallidum in the antiaversive effects of anxiolytics in various models of anxiety.

In conditions in which rats had a free choice between dark and light chambers, microinjections of glutamic acid, serotonin, and campiron into the globus pallidus showed that these agents have antiaversive properties in a threatening situation test but not in an illuminated area test. Dopamine, apomorphine, GABA, chlordiazepoxide, phenibut, and indoter injected locally into this formation of the basal ganglia had no effect on the mechanisms of voluntary movement but counteracted anxiety states in both behavioral models. These results provide evidence that the monoaminergic and aminoacidergic systems of the dorsal pallidum have different functional roles in the operative regulation of behavior for aversive stimuli of different modalities.

[Neurochemical features of the ventral pallidum in realization of the antiaversive effects of anxiolytics in different models of anxiety].

Preliminary intraperitoneal injections of some combinations of adreno- and dopaminomimetics, monoamines, and mediator amino acids (as well as of their agonists and antagonists) followed by microinjections of the same combinations into the ventral pallidum reveal differences in the functional significance of the neurochemical profile of this paleostriatum formation in realization of the anxiety states of different genesis, as manifested in the "illuminated site avoidance" and the "threatening situation" tests in rats. The pharmacological analysis based on the local injection of anxiosedative and anxioselective agents into the ventral paleostriatum showed that the antiaversive action of campirone is revealed under the conditions of dominating fear motivation, while that analogous action of chlordiazepoxide, phenibut and indoter is revealed under negative stressful zoosocial impacts and is realized by serotonin- and GABA-ergic (rather than by cathecholamine- and glutaminergic) aversive systems of the ventral pallidum.

Neurochemical characteristics of the ventromedial hypothalamus in mediating the antiaversive effects of anxiolytics in different models of anxiety.

In experiments on rats using an "illuminated area" avoidance test and a "threatening situation" avoidance test, preliminary i.p. administration and subsequent microinjection into the ventromedial hypothalamus of various combinations of monoamines, transmitter amino acids, and their agonists and antagonists demonstrated differences in the functional importance of the neurochemical profile of this limbic formation in mediating anxiety states of different origins.