[Effect of +Gz-induced cerebral ischemia on the distribution of nitric oxide synthase in rabbit brain]

In order to study the effect of repeated short termed + Gz -induced cerebral ischemia on rabbit brain, rabbits were exposed to +4.0 Gz for 3 times (with 30 min interval in between) which caused the arterial pressure at eye level dropped to 0 kPa and lasted for 30 s. Changes of distribution of the nitric oxide synthase(NOS) positive neurons in rabbit brain were observed using the NADPH-diaphorase histochemical reaction. The results showed that NOS positive neurons in the parietal cortex, piriform cortex, hippocampus and dentate gyrus increased by 167%, 126%, 321%, 172% (P < 0.01) respectively, immediately after repeated + Gz exposures, as compared with those of controls. It still remained significantly more than that in controls (P < 0.01) 1 h and 6 h after exposure. It suggests that NO may have some effect on the neurons during cerebral ischemia.