Author + information
- Received June 3, 1985
- Revision received August 20, 1985
- Accepted September 3, 1985
- Published online February 1, 1986.
- Jose M. Brum, MD,
- Alfred A. Bove, MD, PhD, FACCa,
- Qian Sufan, MD,
- William Reilly, BS and
- Vay L.W. Go, MD
- ↵aAddress for reprints: Alfred A. Bove, MD, Cardiovascular Division, Mayo Clinic, Rochester, Minnesota 55905.
Vasoactive intestinal polypeptide, a neurotransmitter peptide detected in animal and human hearts, has been found in nerves of coronary arteries. To determine the amount and distribution of vasoactive intestinal polypeptide in the large coronary vessels and its possible participation in coronary vasoregulation, two groups of animals were studied.
In the first group, 11 anesthetized dogs were sacrificed to collect three (1 cm) segments along the circumflex and left anterior descending coronary arteries. These segments represented proximal (I), middle (II) and distal (III) portions of the two arteries. Concentrations (ng/g) of vasoactive intestinal polypeptide-like immunoreactive substance were determined by radioimmunoassay. Vasoactive intestinal polypeptide-like immunoreactivity was present in the left anterior descending (I = 7.28 ± 1.65, II = 3.74 ± 0.57, III = 2.29 ± 0.53) and circumflex (I = 4.16 ± 1.52, II = 4.58 ± 1.13, III = 4.00 ± 0.81) coronary arteries. The difference in vasoactive intestinal polypeptide-like immunoreactivity among epicardial segments of the anterior descending artery was significant, but there was no significant difference among segments of the circumflex coronary artery.
In the second group (eight closed chest anesthetized dogs), the effects of vasoactive intestinal polypeptide intracoronary infusion on epicardial coronary constriction were examined at rest and with the artery constricted by serotonin. Left anterior descending (segments I, II and III) artery responses (% area change) to vasoactive intestinal polypeptide and vasoactive intestinal polypeptide plus serotonin were examined using quantitative coronary angiography. Vasoactive intestinal polypeptide infusion resulted in significant vasodilation in all the segments (I, II and III) of the left anterior descending artery. However, serotonin-induced large coronary vasoconstriction was not reversed by vasoactive intestinal polypeptide. Vasoactive intestinal polypeptide is an epicardial coronary vasodilator that varies in concentration along the arteries and does not reverse serotonin-induced vasoconstriction.
This study was supported in part by Grants and NS06663B AM34988 from the National Institutes of Health, Bethesda, Maryland and funds from the PepsiCo Foundation, Purchase, New York. It was presented in part at the Young Investigators' Award Competition at the 34th Annual Scientific Session of the American College of Cardiology, Anaheim, California, March 1985 (Dr. Brum was one of the five finalists).
- Received June 3, 1985.
- Revision received August 20, 1985.
- Accepted September 3, 1985.
- American College of Cardiology Foundation