THE EFFECT OF ACETYLCHOLINESTERASE INHIBITOR (SDZ-ENA-713) FOR R-CBF AND FOCAL CEREBRAL-ISCHEMIA

The purpose of the present study was to examine the effect of Acetylch olinesterase inhibitor (AChEI) on r-CBF (group A) and its protecting e ffect on focal ischaemic cell damage (group B). The pial arterial diam eter and the r-CBF were measured with a width analyzer and with a lase r Doppler flowmeter through a cat cranial window on the ectosylvian gy rus. The ischaemic area was measured histologically. We used intraveno us injection of -1-dimethyl-amino)ethyl]-N-methyl-phenylcarbamate, SDZ ENA 713, Sands Pharmacy) to block AChE. Twenty minutes after injectio n AChEI (0.6 mg/kg) the pial arteriole dilated 108.5 +/- 1.8% and the r-CBF increased 115.4 +/- 2.6%. The pial arteriole dilated maximally t o 137.6 +/- 6.5% at 120 minutes after injection and the r-CBF increase d maximally to 137.1 +/- 19.5% at 60 minutes after injection. The prot ecting effect was evaluated using cats and 1 hour of occlusion of the middle cerebral artery (MCA). Twenty minutes after injection of AChEI, the pial arteriole dilated to 116.7 +/- 2.4% and the r-CBF increased to 111.9 +/- 2.6% significantly. During MCA occlusion the r-CBF decrea sed to 24.7-41.4% in group B and 25.1-32.6% in sham group (group C). T he pial arteriole dilated 145.0-184.0% in group C and 150.7-171.6% in group B during MCA occlusion and 30 minutes after reperfusion the pial arteriole returned to 120.0 +/- 3.3% in group C and 123.4 +/- 11.3% i n group B. There were no significant changes in the r-CBF and in the v essel diameter between group B and C during the 2 hours after reperfus ion. But 2.5 hours after reperfusion the pial arteriole began to redil ate prominently in group C and 5 hours after reperfusion the pial arte riole redilated 118.3 +/- 4.2% in group B and 140.0 +/- 3.6% in group C. The percentage of infarcted area in sham animals (group C) measured 38.6 +/- 6.4% and significantly decreased to 26.2 +/- 7.8% in treated animals (group B). In conclusion, AChEI dilates cerebral arteries and increases CBF. AChEI protects ischaemic areas from parenchymal and ve ssel damage because of increasing collateral circulation in focal isch aemia.