A STUDY ON THE SUITABILITY OF HUMAN POSTMORTEM CEREBRAL-ARTERIES FOR THE INVESTIGATION OF NEUROGENIC VASODILATION

The aim of the present study was to determine the feasability of using human postmortem cerebral arteries for the study of neurogenic vasodi lator mechanisms. The cerebral artery rings contracted in response to cumulatively added 5-HT, were completely relaxed by sodium nitroprussi de, but carbachol relaxation exceeded 30% in rings from only two brain s. EFS produced relaxant responses in preparations from eight of the 1 3 brains. In cerebral artery rings from five out of these eight brains , incubation with the NOS inhibitor L-NOArg (100 mu M) produced a mark ed attenuation of the neurally mediated relation (mean values before a nd 30 min after drug addition were 42 +/- 7% and 12 +/- 4% of the 5-HT induced tone respectively, p < 0.01, paired t-test). In conclusion, t here are significant practical problems associated with the use of pos tmortem cerebral arteries because of the inevitability of tissue deter ioration after death and the uncertainty concerning whether this might be more marked for some types of nerves than for others.