Phenylephrine would increase blood pressure by producing vasoconstriction, but this increase of blood pressure would induce bradycardia through stimulation of carotid baroreceptors. Item XIXa Wrong . Go back to Item XI before trying to answer Item XIX again. Item IIa Wrong . Physiological antagonism is caused by agonist and antagonist acting at two independent sites and inducing independent, but opposite, effects.
Atropine acts at the same site as acetylcholine.
Item XVIc Right . Phenelzine inhibits monamine oxidase, the enzyme which metabolizes many biogenic amines. Some kinds of heavy cheese have a high content of substances, mainly tyramine, which can produce an increase in blood pressure. Normally, after ingestion of such cheese, these substances are broken down rapidly by monamine oxidase. In a patient treated with phenelzine, metabolism of these amines is inhibited, and, therefore, they can produce a dangerous rise of blood pressure accompanied by a reflex bradycardia.