ABSTRACT
Dopamine and glutamine acid microinjection in the locus coeruleus of rats does not influence the alarm state in the test of "Threatening situation" avoidance, but weakens the state of alarm in the test of "illuminated site" avoidance. The local injection of GABA and noradrenaline mesatone effect imitators in this brain formation weakens the alarm state in the test of "threatening situation" avoidance but is not effective in the test of "illuminated site" avoidance. On the contrary, the chemical stimulation of locus coeruleus by serotonin influences the anxiolytic effect in two different experimentally modelled states of alarm. The participation of locus coeruleus and acidergic mechanisms in anxiety of diverse aversive genesis is discussed.
Subject(s)
Anxiety/etiology , Avoidance Learning/physiology , Biogenic Monoamines/physiology , Locus Coeruleus/physiology , Receptors, Amino Acid/physiology , Receptors, Cell Surface/physiology , Animals , Anxiety/physiopathology , Avoidance Learning/drug effects , Locus Coeruleus/drug effects , Male , Microinjections , Neurotransmitter Agents/pharmacology , Phenylephrine/pharmacology , Rats , Receptors, Amino Acid/drug effects , Receptors, Cell Surface/drug effectsABSTRACT
The experiments on rats with tests of avoiding "lighting square" and "threatening situation" and with the chemical stimulation of dorsal and ventral hippocampus with dopamine, 5-HT, GABA and glutamine acid, showed different functional significance of these monoamines and acidergic transmitters agents in the states of anxiety of heteromodal aversive genesis. It seems that the variations in the action spectrum of anxiolytics under study are due to unequal degree of 5-HT and GABA-ergic transmitter mechanisms of dorsal and ventral hippocampus.
Subject(s)
Anti-Anxiety Agents/therapeutic use , Anxiety/drug therapy , Avoidance Learning/drug effects , Hippocampus/drug effects , Receptors, Cell Surface/drug effects , Animals , Anxiety/chemically induced , Anxiety/physiopathology , Avoidance Learning/physiology , Chlordiazepoxide/therapeutic use , Disease Models, Animal , Dopamine , Drug Evaluation, Preclinical , Glutamates , Glutamic Acid , Hippocampus/physiopathology , Male , Rats , Receptors, Cell Surface/physiology , Serotonin , gamma-Aminobutyric AcidSubject(s)
Anxiety/physiopathology , Brain/physiopathology , Receptors, Dopamine/physiology , Animals , Anxiety/chemically induced , Brain/drug effects , Disease Models, Animal , Dopamine Agents/pharmacology , Dopamine Antagonists , GABA Antagonists , Male , Microinjections/methods , Rats , Receptors, Dopamine/drug effectsABSTRACT
The 1-(2-pyrimidinyl)-piperazine derivatives campirone, campironine, levopironine) evoked hyperpolarizing responses of rat dorsal root ganglion neurons mediated by 5-hydroxytryptamine(1A) receptor activation and, like chlordiazepoxide, potentiated neuronal responses evoked by GABA-depolarizing receptor activation. The drugs studied in the lighted space and threatening situation avoidance tests showed an anxiolytic effect. Picrotoxin was found to be effective in inhibiting the anxiolytic effect of chlordiazepoxide, levopironine and campironine, but it failed to affect the antianxious action of campirone. Whether the GABA-ergic mechanisms may contribute to the anxiolytic action of 1-(2-pyrimidinyl)-piperazine derivatives.
Subject(s)
Anti-Anxiety Agents/pharmacology , Buspirone/analogs & derivatives , Piperazines/pharmacology , Receptors, GABA-A/drug effects , Animals , Avoidance Learning/drug effects , Buspirone/pharmacology , Chlordiazepoxide/pharmacology , Drug Interactions , Evoked Potentials/drug effects , Ganglia, Spinal/drug effects , Ganglia, Spinal/physiology , Male , Neurons/drug effects , Neurons/physiology , Picrotoxin/pharmacology , Rats , Receptors, GABA-A/physiology , gamma-Aminobutyric Acid/pharmacologyABSTRACT
Microinjections of monoamines and amino acids into rat ventral hippocampus showed functional relevance of GABA- or dopamine- and 5-HT-ergic mechanisms of this structure of brain formed by aversive actions of diverse biological importance rather than glutamate-ergic ones. The participation of hippocampus monoamine- and acidergic mechanisms in the origin of diverse aversive anxiety is discussed.
Subject(s)
Anxiety/etiology , Avoidance Learning/physiology , Hippocampus/physiology , Animals , Anxiety/physiopathology , Avoidance Learning/drug effects , Dopamine/administration & dosage , Glutamates/administration & dosage , Glutamic Acid , Hippocampus/drug effects , Male , Microinjections , Rats , Serotonin/administration & dosage , gamma-Aminobutyric Acid/administration & dosageABSTRACT
In experiments on rats the presence or absence was studied of the phenomenon of potentiation of anxiolytic action, estimated by the time of the animal stay in the light part of the chamber in tests of avoidance of "the lighted ground" or "menacing situation" at combined application of the pairs of substances of benzodiasepine and non-benzodiasepine series (elenium, indoter, campiron and campironin). Spectra of their neurochemical activity were determined in experiments on neurones of isolated spinal ganglia of rats with intracellular biopotentials records. It has been established that GABA-potentiating action of indoter and elenium, dopamine-negative action of campiron and campironin are significant in their anxiolytic action in the states of alarm of aversive genesis of different modalities. Serotoninmimetic effect of non-diasepine tranquilizers is of functional significance in the test of avoidance of "the lighted ground", but not of the "menacing situation". It is suggested that differences of neurochemical mechanisms of anxiolytic action of the tested tranquilizers testify to different neurochemical profiles of the neuronal "matrices" of the studied states of alarm.
