Effect of the EGb 761 (Ginkgo bilboa extract) on primary immune response in experimental chronic stress

The effect of a chronic stress upon the primary immune response on mice was evaluated by using the plaque-forming cells (PFC)-direct technique, which allowed us to record a serious suppression of the immune response in the exposed animals. In the next phase of the experiment a second group was initially treated with Tanakan (EGb 761--Ginkgo biloba extract) and then it was submitted to the same chronic stress: this procedure did not bring about the increase of the number of lymphocytes but it significantly improved the function of these cells.