In which part of the body would you NOT expect to find nicotinic receptors?

Nicotinic receptors are a type of cholinergic receptor that respond to the neurotransmitter acetylcholine. These receptors are primarily found at various locations in the body, particularly where they play a critical role in signaling.

At the neuromuscular junction, nicotinic receptors are essential for muscle contraction, as they facilitate the transmission of nerve impulses to muscle fibers. In the brain, nicotinic receptors are involved in cognitive functions and play roles in addiction and reinforcement. The adrenal glands contain nicotinic receptors as well, as they are stimulated by acetylcholine to release epinephrine (adrenaline) and norepinephrine in response to stress.

In contrast, while the pancreas has a variety of receptors, it does not primarily rely on nicotinic receptors for its functions. Instead, it utilizes other types of receptors, particularly muscarinic receptors, for mediating the effects of acetylcholine, especially in the regulation of insulin secretion. Thus, it is correct to identify the pancreas as a location where nicotinic receptors are not expected to be found.