Within 48 hours of measuring the rADC value of the L-theanine treatment group, the rADC values of the four points of interest all increased with time, and there was a positive correlation between the variables X and Y. In observing the efficacy indicators of L-theanine, the L-theanine treatment group showed a significant advantage in the neurospecific enolase (NSE) content compared with the cerebral ischemia group (P < 0.01). This evidence concerns the gene ENO2 and brain ischemia.