Effects of drugs affecting noradrenergic neurotransmission in rats with spontaneous petit mal-like seizures.

Wistar rats of a strain displaying spontaneous petit mal-like seizures and spike-wave EEG discharged (SWD) were injected i.p. with drugs affecting noradrenergic neurotransmission. The EEG and behavior were recorded. Drugs which decrease alpha-noradrenergic neurotransmission, prazosin (alpha 1-antagonist) and clonidine (alpha 2-agonist), increased SWD and were sedative in a dose-dependent manner. Drugs which increase alpha-noradrenergic neurotransmission, ST 587, cirazoline (alpha 1-agonists) and yohimbine (alpha 2-antagonist), reduced SWD and the latter two caused agitation. Drugs which interact with beta-noradrenergic transmission (salbutamol, isoprenaline and propranolol), monoamine oxidase inhibitors (nialamide and iproniazid), and a noradrenaline reuptake inhibitor (desipramine), did not affect SWD. These findings suggest that noradrenaline participates in the control of petit mal-like seizures in the rat, as in other types of seizures and other animal models.