Beneficial effects of S-113m, a novel herbal prescription, on learning impairment model in mice.

The effects of S-113m, a novel herbal prescription consisting of Biota orientalis, Panax ginseng and Schisandra chinensis, were studied regarding learning and memory performance in the step-down and lever-press tests in normal, as well as in learning-impaired, mice. The prescription had no effect on memory registration, consolidation and retrieval processes or on motor activity in normal mice. However, a single oral administration of S-113m at doses of 250 and 500 mg/kg reduced the ethanol-induced and scopolamine-induced impairment of memory registration in the step-down test. The preparation also improved the electroconvulsive shock-induced impairment of memory consolidation in the same test. S-113m did not, however, attenuate the ethanol-induced impairment of memory retrieval. These suggest that S-113M has a preferential beneficial effect on the impairment of memory registration and memory consolidation rather than on memory retrieval in mice, through direct action on the learning and memory process.