Ribavirin-induced behavioral, body temperature and electrocortical spectra effects in the rat

Behavioral, electrocortical spectra and body temperature effects, following a single intracerebroventricular (i.c.v.) or intraperitoneal (i.p.) injection of ribavirin, were studied in male adult rats. Ribavirin, when administered i.p., induced squatting posture, sedation, electrocortical synchronization, piloerection and a slight decrease of tactile and/or auditory stimuli/responses lasting from 45 min to 16 hr, as well as a longer lasting hypothermic effect. Following i.c.v. administration, ribavirin (50, 100 and 200 micrograms) elicited a soporific effect and produced changes in the electrocortical spectra. Pretreatment, 15 min before, with either prazosin (10 mg/kg, i.p.), an alpha 1-adrenoceptor blocker, or piperoxan (20 mg/kg, i.p.) and yohimbine (1 mg/kg, i.p.), two alpha 2-adrenoceptor blockers, or naloxone (1 mg/kg, i.p.), an opioid antagonist, did not prevent the hypothermic and behavioral effects induced by i.p. or i.c.v. administration of ribavirin. The present findings exclude an involvement of alpha-adrenergic and opioid neurotransmission in mediating the hypothermic, electrocortical and behavioral effects induced by ribavirin.