Abstract
Coronary endothelial dysfunction is characterized by a lower response to endothelium-dependent vasodilators such as acetylcholine (ACh) and serotonin (5-HT), but by an unaltered response to endothelium-independent vasodilators such as nitroglycerin (NTG). In the present study, we investigated the vasoreactivity of the coronary bed in vivo, in a dog model of ischemia and reperfusion (I/R). We also assessed the morphology of the subepicardial arterioles and capillary bed by means of scanning electron microscopy (SEM). Anesthetized, instrumented dogs were divided in two groups. One group (N=27) was submitted to ischemia (60 min) and reperfusion (180 min) of the left circumflex coronary artery, the second group (N=8) was sham-operated. Prior to and following I/R, ACh, 5-HT, and NTG were given intracoronarily. At the end of the experiment a 1 cm3 myocardial biopsy was processed for SEM. The sham-operated dogs showed a reduction of basal coronary flow of 11%, but the vasoreactivity to ACh and 5-HT remained constant. In the I/R group, basal coronary flow was reduced by 35% (p<0.05), and the vasoreactivity to ACh and 5-HT, but not to NTG, was significantly blunted. At SEM the arterioles of the dogs submitted to I/R showed a marked adhesion of leukocytes associated with holes an the endothelial surface, while the capillary bed was free of changes and patent. Thus, following I/R, coronary endothelial dysfunction could be demonstrated in vivo by the blunting of the vasoreactive responses to two different endothelium-dependent vasodilators. The responses to NTG were not affected, probably because the function of the smooth muscle cell was preserved, and the capillary bed was patent.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 3 December 1997, Returned for 1. revision: 2 February 1998, 1. Revision received: 13 February 1998, Returned for 2. revision: 4 March 1998, 2. Revision received: 11 March 1998, Accepted: 11 March 1998
Rights and permissions
About this article
Cite this article
Martorana, P., Goebel, B., Ruetten, H. et al. Coronary endothelial dysfunction after ischemia and reperfusion in the dog: A functional and morphological investigation. Basic Res Cardiol 93, 257–263 (1998). https://doi.org/10.1007/s003950050093
Issue Date:
DOI: https://doi.org/10.1007/s003950050093