Publications of Faculty of Medicine:EFFECT OF KOREAN GINSENG EXTRACT ON SOME BEHAVIOURAL ASPECTS IN STREPTOZOCIN INDUCED DIABETIC RATS AND ITS INTERACTION WITH AN ORAL HYPOGLYCEMIC AGENT( GLICLAZIDE) : Abstract

In this work, induction of diabetes in rats by single intraperitoneal injection of streptozocin (35 mg/kg b.w.) resulted in deterioration of motor coordination evidenced by shortening of time of keeping posture on rolling drum and learning behaviour evidenced by significant increase in latency period requied for development of a conditioned reflex with no affection of extension time. Gliclazide alone Significantly improved motor coordination with no effect on learning behaviour. This was associated with partial improvement of carbohydrate metabolism in the form of disappearance of ketonuria. Coadministration of ginseng either in low (25 mg/kg b.w.) or high (100 mg/kg b .w.) doses normalized both motor and learning behaviour in diabetic rats. The latter effect was not related to any change in the studied neurotrasmitters ( notepinephrine or acetyl choline) concentrations. Glucose level was not significantly affected by gliclazide and ginseng combination in spite of the significant potentiation of glucose stimulated insulin release. This may imply that the beneficial effect on motor behaviour may be related to insulin induced improvement in intracellularutilization of glucose but its magnitude was not sufficient to normalize blood glucose level. reflex as well as neurotransmitter levels namely•norepinephrine and acetylcholine in cerebral cortex and thalamus & hypothalamus.The choice of the studied neurotransmitters and brain areas was based on relative importance in the investigated cerebral functions. The metabolic parameters included fasting serum glucose level, basal and stimulated insulin release by isolated B cells of pancreas. Two doses of ginseng were used (25 mg/kg. BW and 100 mg/kg. BW) which represented the lowest and highest extreme range of doses used in previous experimental studies in intact animals (Petrov et al., 1978 & Petrov 1993) . It is coping with the rodent equivalent of average human dose according to Pajet and Barnes (1964) as well as pilot experiments previously done in our laboratory.