Protective role of ascorbic acid in hemorrhage-induced cardiovascular depression.

Haemorrhagic shock is associated with hyperproduction of free radicals. Hence ascorbic acid (AA), a free radical scavenger, may be of benefit in such cases. We investigated in Wistar rats the role of free radicals in causing cardiovascular depression and the protective role of ascorbic acid, if any, in acute haemorrhage. The rats were catheterized for recording hemodynamic parameters. Acute haemorrhage was induced through phlebotomy followed by resuscitation. The test group received AA for 3 days before inducing haemorrhage and was resuscitated with AA and Ringer's lactate. The controls received only ringer lactate. Malondialdehyde was estimated to assess free-radical production. All rats showed significant fall in cardiovascular parameters with simultaneous increase in MDA level. While all rats showed significant improvement following resuscitation, the recovery was greater in the test group. The MDA levels decreased significantly in the ascorbic acid treated group. Our results demonstrate the involvement of free radicals in hemorrhage-induced cardiovascular depression and the cardio-protective effect of ascorbic acid.