Impaired microvascular filling after focal cerebral ischemia in the monkey

H Recent experimental studies have shown that obstructive changes in the cerebral microvasculature may be a major factor limiting recovery from temporary This impaired filling of the microvasculature after transient cerebral ischemia has been termed the "no reflow" phenomenon,' and increased blood viscosity and occlusive changes in and near the terminal blood vessels probably play major roles in its genesis. ,4 The initial studies on the no reflow phenomenon utilized global cerebral i ~ c h e m i a , ' ~ , ~ and it was shown that appropriate treatment can diminish or abolish impaired vascular filling2 a 3 A recent investiga t ion from this laboratory demonstrated impaired microvascular filling after focal cerebral ischemia in the m ~ n k e y , ~ and the present study was designed to determine whether improper vascular filling in this preparation can be modified by suitable treatment modes. Because low-molecular -weight d e x t r a n (LMWD),7-' heparin,' 2-1 hypocapnia,' and surgical restoration of flow through large parent vessel^^,^.' 7 2 0 are thought to alleviate the effects of focal ischemia, the impact of these therapeutic measures upon impaired microvascular filling after focal ischemia was examined.