Uncertain Role of Camp in Platelet Function

To the Editor: The recent article by Dr. Salzman on cyclic AMP and platelet function (N Engl J Med 286:358, 1972) contained several points that are at present controversial and therefore require comment. The major premise was that agents that inhibit platelet function increase platelet cyclic AMP whereas agents that stimulate platelet activity decrease platelet cyclic AMP. The article failed to indicate, however, that this hypothesis is based almost entirely on the effects of various aggregating agents on platelets whose cyclic AMP levels are already artificially elevated by incubation with prostaglandin E₁ (PGE₁).^{1 2 3 4} This would suggest the.