Effects of piracetam on indices of cognitive function in a delayed alternation task in young and aged rats.

The effects of piracetam (64, 128, and 256 mg/kg PO) on the performance of a delayed alternation in a Skinner Box were investigated. Test sessions consisted of 36 trials during which animals were first presented with a single lever (left or right) followed 5, 10, or 20 s later by two levers. A press on the lever opposite to that presented previously (nonmatching to sample) was rewarded.

Combined effects of diazepam and melatonin in two tests for anxiolytic activity in the mouse.

The effects of behaviorally nonactive doses of melatonin and diazepam were investigated in two test models for anxiolytics in mice to see whether mutual enhancement could be observed when the two treatments were combined. The test models used were the four plates test and the tail suspension test. In the former test anxiolytics increase the number of punished crossings and in the latter increase the duration of immobility of mice suspended by the tail.

Behavioral indices of beta receptor subsensitivity after chronic treatment with viloxazine in the mouse.

The aim of the experiments was to determine whether chronic pretreatment with viloxazine decreased the sensitivity of mice to the sedative effects of a beta agonist clenbuterol. Mice were subjected to chronic oral treatment with viloxazine (128 mg/kg twice daily) and then given a single administration of 32 mg/kg PO followed by clenbuterol (0.125 mg/kg IP) before being tested in a standard photocell activity meter.

Effects of an extract of Ginkgo Biloba (EGB 761) on "learned helplessness" and other models of stress in rodents.

The effects of repeated oral administration of an extract of Ginkgo Biloba (EGB 761) on various behavioral models of stress in rodents were investigated. The models in rats included "learned helplessness," shock-suppressed licking (Vogel conflict test) and forced swimming-induced immobility ("behavioral despair"). The models in mice included shock-suppressed exploration (four plates test), spontaneous exploration (staircase test) and food consumption in a novel situation (emotional hypophagia).

Absence of amnesia induction in mice with hydroxyzine in comparison with three other minor tranquillizers.

Hydroxyzine (Atarax) was compared with three traditional anxiolytics (diazepam, meprobamate, triazolam) for potential amnesic activity in a step-through passive avoidance task in the mouse. The doses investigated were: hydroxyzine (4, 8 and 16 mg/kg); diazepam (0.25, 0.