Abstract
To the Editor.— There is general agreement that substances that inhibit platelet aggregation tend to be associated with a rise in platelet cyclic adenosine monophosphate (cAMP), and those that stimulate platelet-clumping with the reverse. 1 Epinephrine reduces platelet cAMP by inhibition of adenyl cyclase. Like epinephrine-induced platelet aggregation, this phenomenon is an α-adrenergic effect, being subject to blockade by phentolamine. 2 Hampton et al 3 discovered that propranolol inhibited noradrenaline-induced platelet aggregation. Propranolol proved also to be a powerful inhibitor of adenosine diphosphate (ADP)-induced aggregation and of potentiating effect of epinephrine on the second phase of ADP-induced aggregation. 4 It seems that this effect would be not related to β-blocking activity but to a stabilizing action on biological membranes like imipramine and related compounds. 5 In regard to its cardiac effects, propranolol appears to have a more evident activity on the inhibition of platelet aggregation.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: JAMA: The Journal of the American Medical Association
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
