INDUCTION OF NADPH-DIAPHORASE ACTIVITY IN THE FOREBRAIN IN A MODEL OFINTRACEREBRAL HEMORRHAGE AND ITS INHIBITION BY THE TRADITIONAL CHINESE MEDICINE COMPLEX NAO YI AN

Induction of NADPH-diaphorase (NDP) activity in the rat cerebral corte x was studied after autologous blood injection into the internal capsu le as experimental model of intracerebral hemorrhage. The potential in hibitory effect on NDP induction by Nao Yi An (NYA), a complex derived from materials of animal and plant origin used in the treatment of in tracerebral hemorrhage in traditional Chinese medicine, was also inves tigated, In animals without therapeutic treatment 2 and 4 days after i njection of autologous blood, NDP activity was highly induced in pyram idal neurons in the neocortex, piriform, and entorhinal cortices, in a strocytes and in phagocytes in the hematoma and the area surrounding i t, as well as in the subcortical white matter, and in endothelial cell s in both the cortex and subcortical white matter bilaterally. Oral ad ministration of NYA failed to inhibit NDP induction in endothelial cel ls but demonstrated a strong inhibitory effect on NDP activity induced in pyramidal neurons and astrocytes, NDP induction in phagocytes was also inhibited by the administration of NYA. Altogether the present re sults suggest that intracerebral hemorrhage in the internal capsule ma y induce nitric oxide synthase activity in different cell populations in the cortex and that administration of NYA can selectively inhibit s uch induction and, thus, potentially play a neuroprotective role. Copy right (C) 1997 Elsevier Science Inc.