J Korean Neurosurg Soc.  1996 Mar;25(3):449-461.

Fluorescence Videomicroscopy Reveals Increased Leukocyte Adherence in Piglet Pial Venules During Reperfusion Following Global Cerebral Ischemia

• Park CO

Abstract

We developed an in vivo model of cerebral ischemia-reperfusion wherein on-line videoimages of fluorescently-labelled leukocytes following within pial venules of anesthetized newborn pigs can be obtained. A closed cranial window was implanted over the parietal cortex, and venules were imaged with an fluorescence microscope(Olympus BHMJ) outfitted with a 100 watt mercury lamp, rhodamine filter cube. 10 x immersion lens(Olympus; 0.4NA), and newvicon tube camera. Final image magnification captured to Super VHS videotape was 470x. Rhodamine 6G was administered as a 0.5mg/kg i.v. loading dose and a 0.5mg/kg/h i.v. maintenance dose in saline to selectively label circulating leukocytes. We made an ideal model with 6 piglets and under basaline conditions in piglets, few labelled leukocytes were observed adhering to the endothelium of 50-60 microm diameter venules. However, following 10min, of global cerebral ischemia induced by reversible subclavian and brachiocephalic occlusion, a dramatic increase in rolling and adherent leukocytes was observed at 30, 60, and go on, of reperfusion. At these times, cortical blood flow, measured by both laser doppler flowmetry and hydrogen clearance, was decreased by 25-40%(p<0.05). There findings demonstrate the feasibility of continuous in vivo monitoring of leukocyte adherence in cerebral venules, and suggest that reperfusion-induced adherence to venular endothelium may contribute to hypoperfusion following global cerebral ischemia.

Keyword

Leukocytes; Cortical blood flow; Ischemia-reperfusion; Laser doppler flowmetry; Hydrogen clearance; Rhodamine 6G

MeSH Terms

Brain Ischemia*
Endothelium
Fluorescence*
Humans
Hydrogen
Immersion
Infant, Newborn
Laser-Doppler Flowmetry
Leukocytes*
Microscopy, Video*
Rabeprazole
Reperfusion*
Rhodamines
Swine
Venules*
Videotape Recording
Hydrogen
Rhodamines