The Influence of Adrenaline on Gender Difference in Adenosine Diphosphate-Induced Aggregation of Platelets in the Rat

Summary

The role of adrenaline on the inhibitory effects of physiological levels of oestradiol on ADP-induced intravascular aggregation has been studied. Platelets from pro-oestrous female rats aggregated less than those from dioestrous and male rats. Following adrenalectomy, there was no longer any difference(s) in the aggregability of the platelets to ADP in any of the rats. Adrenaline infusion (20 mg kg⁻¹ hr⁻¹) restored platelet aggregation to preadrenalectomy levels in pro-oestrous rate. Measurement of spontaneous fibrinolytic activity of the plasma showed highest value in pro-oestrous rats. Adrenalectomy reduced, while adrenaline infusion increased the fibrinolytic activity. The results suggest that the inhibitory effects of oestradiol on intravascular aggregation are dependent on endogenous adrenaline possibly working through the fibrinolytic pathway.

Keywords

Intravascular aggregation - Oestradiol - Adrenalectomy - Adrenaline - Fibrinolysis

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