Abstract
Rings from greyhound large (3-4 mm internal diameter) and small (less than 200 μ m internal diameter) coronary arteries were mounted in water-jacketed tissue baths or a Mulvany myograph, respectively. Relaxations to ATP and adenosine were determined in arteries precontracted with the thromboxane A2 mimetic U46619 or with K+, ATP was a much more effective relaxant of large arteries than adenosine. ATP relaxed large coronaries by an endothelium-dependent mechanism whereas relaxations to adenosine were not endothelium-dependent. In contrast, adenosine appeared to be slightly more effective than ATP in relaxing small coronary arteries. Moreover, adenosine was more effective in relaxing K+-contracted small coronaries than K+-contracted large coronary arteries. These results suggest that ATP may be a more significant relaxant of large coronaries than adenosine but that adenosine may be a more significant relaxant than ATP in small coronary arteries.
| Original language | English |
|---|---|
| Pages (from-to) | 119-126 |
| Number of pages | 8 |
| Journal | European Journal of Pharmacology |
| Volume | 143 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - Nov 3 1987 |
| Externally published | Yes |
Bibliographical note
Funding Information:This research was funded by the Medical Research Council of Canada and an Institute Grant from the National Health and Medical Research Council of Australia to the Baker Medical Research Institute. T.D.W. was a M.R.C. of Canada Visiting Scientist.
ASJC Scopus Subject Areas
- Pharmacology
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't