Contractile Response to Endothelin in Porcine External Carotid Arteries. |
J H Shim, Y K Park, Y G Chong, H S Jung, J K Suh, H K Lee, J W Chu, K C Lee |
Departments of Neurosurgery, College of Medicine, Korea University, Seoul, Korea. |
|
|
|
ABSTRACT |
An endothelium-derived 21-residue vasoconstrictive peptide, endothelin, has been isolated, and shown to be one of the most potent vasoconstrictors. We have studied the vasoconstrictor properties of endothelin in porcine external carotid artery strips and compared the maximal contractile response with other vasoactive compounds such as KCI and prostaglandin F2 alpha. Endothelin typically produced an intense, sustained increase in vascular tone over a dose range similar to that seen with other vasoconstrictor substances such as KCI and prostaglandin F2 alpha.
Cumulative addition of the peptide to the tissue bath caused dose-dependent contraction. The contractile response to each addition of the peptide was typically gradual and sustained.
And during the washing procedure, it was observed that the contractile response to endothelin was resistant to drug removal. The dose of endothelin that produced a half-maximal contraction for porcine external carotid artery was 10-8.3M.
The response was inhibited to the several antagonists of glyceryl trinitrate, nitroprusside, verapamil, nimodipine, nifedipine, acetylcholine, prostagladin I2. |
Key Words:
Endothelin; Vasospasm; Porcine artery |
|