0
We're unable to sign you in at this time. Please try again in a few minutes.
Retry
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
Retry
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
ARTICLE |

Why a Little Aspirin Is Better Than a Lot

Beverly Merz
JAMA. 1987;257(16):2135. doi:10.1001/jama.1987.03390160021008.
Text Size: A A A
Published online

ABSTRACT

WHILE CLINICAL investigators continue their empirical search for the optimum aspirin dose to prevent thrombogenesis, basic researchers have been looking at the effect of aspirin on two prostaglandins that are instrumental in clot formation.

Laboratory studies have determined that aspirin inhibits the production of cyclo-oxygenase, an enzyme that is essential for the production of thromboxane (TXA2), which promotes platelet aggregation, as well as for the synthesis of prostacyclin (PGI2), which inhibits platelet aggregation.

Fortunately, aspirin's effects on TXA2, which is produced by platelets, are longer lasting. Because platelets are not capable of producing new supplies of cyclo-oxygenase, the resumption of TXA2 production requires 48 hours— the time it takes to release a new generation of platelets.

In contrast, PGI2 is produced by endothelial cells, which are capable of cyclo-oxygenase production. As soon as aspirin therapy is discontinued, the endothelium resumes cyclo-oxygenase production. As a result,

Topics

Sign in

Create a free personal account to sign up for alerts, share articles, and more.

Purchase Options

• Buy this article
• Subscribe to the journal

Figures

Tables

References

Letters

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.

Multimedia

Some tools below are only available to our subscribers or users with an online account.

Sign in

Create a free personal account to sign up for alerts, share articles, and more.

Purchase Options

• Buy this article
• Subscribe to the journal

Related Content

Customize your page view by dragging & repositioning the boxes below.

Jobs
brightcove.createExperiences();