Effects of selected drugs on spontaneously occurring abnormal behavior in beagles

A sub-population of beagles with abnormal behavioral patterns has been identified, isolated and tested for responsively to selected classes of psychoactive drugs. The abnormal behavior was ameliorated by anxiolytics and antidepressants but not by antipsychotics, an antihistaminic, an alpha-adrenergic blocker, a beta-adrenergic blocker, or an anticholinergic drug. Improvement occurred after a single dose of the anxiolytic drugs but did not occur until 10-18 days after daily dosing with standard tricylic antidepressants and the MAO inhibitor isocarboxazid. This delayed onset in beagles resembles that seen on use of these drugs in humans. The results with these drugs suggest that the abnormal behaviors of the beagles are related to anxiety and are in part depressive in nature. This colony provides an animal model of abnormal behavior which allows evaluation of the anxiolytic and antidepressant effects of drugs and estimates of the onset of action of antidepressant drugs.