AIM: To observe the protective effects of
compound of Ginkgo biloba extract on cerebral functional decline mice induced
by glucocorticoid. METHODS:The mice of 6 mo were injected subcutaneously of hydrocortisone 30 mg·kg -1 every other day, 11 times totally, to create cerebral functional decline model. Jumping stand and water maze test were adopted to estimate the learning and memory
abilities of mice. The body weight, spleen index and thymus index were also assayed. RESULTS: Compared with the control group, the learning and memory abilities of the model mice declined significantly. In jumping stand test, the period for reflect, latency, stagnant period, and error times were (2.4±1.9)s, (41±81)s, (13±14)s , (2.5±2.4) respectively. In memory ability assay, the latency, stagnant period, and error times were (159±144)s, (3±4)s, (0.6±1.0) respectively. In water maze test, times for mice arriving to point B were (61±37)s, and error times were (3.2± 2.4), to point C were (65±65)s and error times (3.9± 2.9) respectively during learning ability assays. The data for up-grading were (60±41)s, (3.0± 1.0), (71±59)s and (3.2±2.2) in memory ability assay, P<0.05, P<0.01. Body weight lost in model mice(37±4)g and spleen index decreased ((66± 31) mg·10 g -1 body weight). Thymus index only showed decreasing trend. All three compounds of Ginkgo biloba extract doses of 15, 30, 60 mg·kg -1 could improve the learning and memory abilities of model mice to different degrees (P<0.05, P< 0.01). 60 mg· kg -1 could also restrain the decrease of body weight ((40±3)g, P<0.05) and increase spleen index ((98±33) mg·10 g -1 body weight, P< 0.05 ). The effect of the prescription on the thymus index of model mice was not shown in this study. CONCLUSION:
Compound of Ginkgo biloba extract can ameliorate the learning and memory abilities of cerebral functional decline mice induced by glucocorticoid obviously. The highest dose can impede the immunosuppressive action and body weight loss.