Platelet Changes after Adrenaline Infusions with and without Adrenaline Blockers

Abstract

Adrenaline infusions into young, healthy, male subjects produced a rise in both platelet counts and platelet adhesiveness. Pronethalol, a ß-blocker of adrenaline, blocked these changes. Phentolamine, an α-blocker, produced a fall in platelet count which interfered with the interpretation of its blocking effect. The results suggested however, that Phentolamine did not prevent the increase in platelet adhesiveness produced by adrenaline. ^* R. Samuel McLaughlin Travelling Fellow. Present address: Hospital for Sick Children, Toronto 2, Ontario, Canada.