This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Tolazoline is used as - 
Select and explain. 
A. As thrombin inhibitor in peripheral angiography, B. As vasodilator in treating coronary aery stenosis during angio procedures, C. As vasoconstrictor in t/t of varices, D. Antispasmodic during biliary spasm
B: As vasodilator in treating coronary aery stenosis during angio procedures
Answer: B: As vasodilator in treating coronary aery stenosis during angio procedures 
Explanation: Ans. is 'b' i.e., As vasodilator in treating coronary aery stenosis during angio procedures o Tolazoline is a competitive a receptor antagonist and has similar affinities for al and a2 receptors. It is a vasodilator and is quite similar to phentolamine but less potent. Vasodilatory action is due to increase in histamine secretion.