Effects of 2-nicotinamidethyl nitrate (SG-75) and/or nitroglycerin on systemic hemodynamics and coronary blood flow in conscious dogs.

The effect of 2-nicotinamidethyl nitrate (SG-75), a newly synthesized nitroester, on hemodynamics and coronary circulation was studied in conscious dogs, comparing it with nitroglycerin (NG). Dogs were previously instrumented with catheters in the aorta and left atrium and a Doppler flow probe on the left circumflex coronary artery. Percent increases in coronary flow rate were 11 (10 micrograms/kg), 20 (50 micrograms/kg), 71 (100 micrograms/kg) and 169% (200 micrograms/kg) in SG-75 and 3 (1 microgram/kg), 28 (5 microgram/kg), 65 (10 micrograms kg) and 99% (20 micrograms/kg) in NG, thus the dose ratio for an equivalent increase in mean coronary flow is about 10:1 between SG-75 and NG.