Effect of intracarotid hyperosmolar mannitol on cerebral cortical arterioles--a morphometric study.
The morphometric response of cerebral cortical arterioles to intracarotid hyperosmolar mannitol was assessed utilizing a technique of rapid freezing of rat brain tissue in vivo. A significant decrease in the wall to lumen (W/L) ratio was noted in the small parenchymal arterioles (20-49 mu) (p less than .0001) ipsilateral to the mannitol infusion. Larger arterioles showed a decreased W/L ratio but this change was not significant. Control infusion of 0.9% NaCl resulted in no change in arteriolar caliber. These results indicate that intracarotid hyperosmolar mannitol causes a direct vasodilatory response in small cerebral cortical arterioles.
D000818:Animals; D001160:Arterioles / Q000033:anatomy & histology / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D002342:Carotid Artery, External; D002343:Carotid Artery, Internal; D002540:Cerebral Cortex / Q000098:blood supply* / Q000187:drug effects; D007261:Infusions, Intra-Arterial / Q000379:methods; D008297:Male; D008353:Mannitol / Q000008:administration & dosage / Q000494:pharmacology*; D009994:Osmolar Concentration; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D051381:Rats; D011919:Rats, Inbred Strains
D002245:Carbon Dioxide; D008353:Mannitol; D010100:Oxygen