Which of the following is NOT one of the stimulatory effects of nicotine?

Nicotine is known for its stimulatory effects on the body, impacting various physiological processes. One of the primary effects of nicotine is to increase heart rate, which makes the option indicating decreased heart rate inaccurate in the context of nicotine's pharmacological action. When nicotine activates nicotinic acetylcholine receptors, it leads to the release of neurotransmitters such as norepinephrine and dopamine, which stimulate the cardiovascular system, consequently increasing heart rate.

In contrast, nicotine has been documented to suppress appetite, promote urinary retention, and enhance cognitive functions by improving attention and memory. These effects are consistent with its role as a stimulant. Thus, the correct answer identifies decreased heart rate as not being aligned with the stimulatory profile of nicotine, making it the clear choice for the question presented.