RESUMEN
Aquatic, 20% alcoholic & 95% alcoholic extractions of the aeri -al parts of Gynostemma pentaphyllum from Guangdong Provin -ce contain several gypenosides as same as some ginsenosides. The effects of the extractions and gypenoside Ⅲ (ginsenoside Rb 1 ) on memory in mice were studied using one trial passive avoidance responses. Results indicated that Gynostemma pentaphyllum improved impairment of acquisition of memory produced by anisodine, and disruption of consolidation of memory caused by cycloheximide and chlo-ramphenicol. Gynostemma was capable of antagonizing alcoh cl-induc- ed deficit of retrieval. Similar effects were observed with Rb1 in the impairments of acquisition of memory caused by alcohol and pen-tobarbitone sodium. It is clear that Gynostemma pentaphyllum may be an effective memory-enhancing agent.