MEASUREMENT OF THE OXIME HI-6 AFTER PERIPHERAL ADMINISTRATION IN TANDEM WITH NEUROTRANSMITTER LEVELS IN STRIATAL DIALYSATES - EFFECTS OF SOMAN INTOXICATION

In the present study, the technique of microdialysis combined with tan dem high-performance liquid chromatography was used to determine the s triatal levels of HI-6 and neurotransmitters following peripheral admi nistration of HI-6 (50 mg/kg i.m.) in conscious, freely moving rats. T he results were compared with those obtained in animals given soman (1 35 mu g/kg i.p.) 1 min before HI-6 (50 mg/kg i.m.). Principal componen t analysis was used to study the effects of the different treatments o n neurotransmitters and signs of poisoning. In all animals given HI-6, maximum levels of HI-6 appeared in the second 20-min fraction after a dministration of HI-6, then gradually declined, reaching the lower lim its of detection after 3 hr. There was a correlation between severity of poisoning and neurochemical changes observed; dopamine and GABA lev els increased as the severity of signs of poisoning increased. These r esults clearly demonstrate that HI-6 can penetrate into the brain of c ontrol and soman-intoxicated animals. Tandem measurement of dopamine e lectrochemically and HI-6 by UV detection provides a simple method for obtaining data on HI-6 penetration into the brain in neurochemical st udies of soman poisoning and its treatment.