JOURNAL ARTICLE

Effects of antioxidants on the blood-brain barrier and postischemic hyperemia

E Tasdemiroglu, P D Christenberry, J L Ardell, R B Chronister, A E Taylor
Acta Neurochirurgica 1994, 131 (3-4): 302-9
7754839
The role of free oxygen radicals in blood-brain barrier (BBB) disruption and postischemic hyperemia was evaluated in the rabbit model of focal cerebral ischemia-reperfusion. Six groups of rabbits underwent clipping of the anterior cerebral, middle cerebral, and intracranial internal carotid arteries. Cerebral blood flow (CBF) was measured by using radiolabeled microspheres, before, during, and 15 minutes after 1-hour occlusion of these arteries. After 50 minutes of ischemia, Group 1 animals (control) received a placebo. Animals in Groups 2-4 received one of three drugs: catalase at 10 mg/kg, methimazole at 5 mg/kg, or indomethacin at 10 mg/kg. A fifth group received a tungsten-supplemented diet for 14 days before ischemia was induced, and a sixth group was sham operated. Microvascular integrity within the brain was determined by the presence or absence of Evan's Blue (EB)-albumin dye leakage across the BBB and was measured by microspectrofluorometry. In the control group during ischemia, CBF dropped to 14%, 7%, and 11% of preischemic levels in rostral, middle, and caudal sections of the brain, respectively, as characterized by extensive EB-albumin dye leakage through the BBB into the ischemic hemisphere. During early reperfusion, postischemic hyperemia was associated with an increase in CBF of 128%, 123%, and 129% of control in the rostral, middle, and caudal sections of the brain, respectively. In all treated groups and in the group receiving a tungsten-supplemented diet, BBB integrity was protected during reperfusion without inhibition of postischemic hyperemia. This study suggests that early disruption of the BBB to large molecules is mediated by free oxygen radicals, which inhibit rather than cause postischemic hyperemia.

Full Text Links

Find Full Text Links for this Article

Discussion

You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read
7754839
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"