beta-CCM inhibits muricide induced by olfactory bulbectomy in rats

Benzodiazepine site inverse agonists and locomotor activity in rats: bimodal and biphasic influence

Benzodiazepine site inverse agonists may increase or decrease locomotor activity in rodents, depending on the experimental settings. We have compared the behavioral responses to environmental novelty of rats treated with the non-selective inverse agonist DMCM (2 mg/kg) and the alpha1-subunit affinity-selective inverse agonist 3-EBC (15 mg/kg). The behavior in spontaneous locomotor assay (during 45 min) and elevated plus maze (EPM) was automatically recorded. In the EPM, general activity-related parameters were similarly decreased, whereas only DMCM inhibited open-arm activity. In the locomotor assay, both compounds depressed locomotion in the first 15 min and activity in the central zone of the chamber. However, the influence of 3-EBC was less pronounced. The alpha1-subunit selective antagonist beta-CCt (15 mg/kg) attenuated locomotor depression, but not the central-zone avoidance elicited by DMCM. When habituated to the chamber, DMCM-treated animals emitted a plateau phase of activity, which disappeared by adding beta-CCt. Hence, inhibition of activity in exposed areas may be mediated by non-alpha1-subunits, whereas both alpha1 and non-alpha1-subunits may participate in suppression of activity in more protective areas of an apparatus. Hyperlocomotion in habituated animals may depend primarily on the alpha1-subunit. Moreover, the bimodal influence of inverse agonists on locomotion can be biphasic, observable in the same experiment.

The aggression theory of schizophrenia: revisited

The aggression theory of schizophrenia is a psychoanalytic theory which proposes that schizophrenia results from uncontrolled, deprivation-induced aggressive impulses. An animal model of the aggression theory is presented using predatory aggression as the source of arousal. Although neurochemical control of predatory aggression is nonspecific, anatomic control is located in the lateral hypothalamus across species. The lateral hypothalamus also controls schedule-induced polydipsia which has been implicated in schizophrenia. The aggression theory could be empirically evaluated by determining if schizophrenics respond differently than normals to scheduled feedings. Implications of the aggression theory are discussed.