The Appearance of “Exhausted” Platelets at the Time of Stroke in Stroke-Prone Spontaneously Hypertensive Rats

Summary

Stroke was induced in stroke-prone spontaneously hypertensive rats (SHRSP) by NaCl loading. They were killed at 3 weeks and cerebral lesion was confirmed by autopsy. About 2/3 of them had strokes. Platelet count and thrombin-induced aggregation were reduced to 36% and 66%, respectively, compared with the level of those in the healthy SHRSP group which did not have stroke with the same treatment. ADP and serotonin content in platelets diminished by 45% and by 65%, respectively, due to stroke while plasma thiobarbituric acid reacting substances (TBARS, lipid peroxides) in the stroke group was two-fold that in the healthy group. Blood TBARS levels were significantly higher in rats with lower platelet serotonin content than in rats with normal serotonin content. These results suggest that marked activation of platelets has occurred due to vascular injuries at the time of stroke with a consequent decrease in platelet serotonin content and increase in plasma TBARS.

Key words

SHRSP - Serotonin - TBARS - Exhausted platelets at stroke

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