What was the result of adding pilocarpine regarding heart rate?

Pilocarpine is a medication known to stimulate the parasympathetic nervous system by mimicking the action of acetylcholine. When pilocarpine is administered, it typically enhances vagal tone, which in turn lowers the heart rate. This is because stimulation of the parasympathetic system slows down the firing of the sinoatrial (SA) node, the natural pacemaker of the heart.

In the context provided, the heart rate's decrease from 62 beats per minute to 47 beats per minute upon administration of pilocarpine illustrates this mechanism effectively. The drop in heart rate is a direct consequence of the increased parasympathetic activity induced by the drug. Understanding this effect underlines the importance of the autonomic nervous system in regulating heart rate, especially how the parasympathetic system can lead to a reduction in heart rate under certain circumstances.