Autonomic Pharmacology USMLE Step 1 Practice Question
An investigator is developing a drug that results in contraction of the pupillary dilator muscle when instilled topically. The drug works by increasing neurotransmitter release from the presynaptic nerve terminal. When administered intravenously, this drug is most likely to have which of the following additional effects?
Answer choices
- AAcceleration of gut peristalsis
- BRelaxation of the bladder neck sphincter
- CRelease of epinephrine by the adrenal medulla
- DSecretion of sweat by exocrine glands
- EIncrease in pyloric sphincter toneCorrect answer
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