What is the effect of increased parasympathetic tone on ureteral peristalsis?

What is the effect of increased parasympathetic tone on ureteral peristalsis?

• A. Decreases ureteral peristalsis
• B. No effect on ureteral peristalsis
• C. Increases ureteral peristalsis (correct)
• D. Causes ureteral dilation

Answer: (C)

Increased parasympathetic tone boosts ureteral smooth muscle contractions. The parasympathetic system releases acetylcholine that acts on muscarinic receptors in the ureter, making the smooth muscle contract more rhythmically and strongly. This enhances peristaltic waves, helping propel urine from the kidney down into the bladder. Dilation of the ureter isn’t the direct effect of heightened parasympathetic activity, and sympathetic input tends to oppose peristalsis, so the net effect of more parasympathetic signal is to increase peristaltic propulsion.

Increased parasympathetic tone boosts ureteral smooth muscle contractions. The parasympathetic system releases acetylcholine that acts on muscarinic receptors in the ureter, making the smooth muscle contract more rhythmically and strongly. This enhances peristaltic waves, helping propel urine from the kidney down into the bladder. Dilation of the ureter isn’t the direct effect of heightened parasympathetic activity, and sympathetic input tends to oppose peristalsis, so the net effect of more parasympathetic signal is to increase peristaltic propulsion.