👉 The term "nicotinic" is a molecular concept in pharmacology and physiology, specifically related to the neurotransmitter nicotinamide adenine dinucleotide. Nicotinic acetylcholine receptors are involved in the transmission of information from the nervous system. When a person inhales or exhales, their respiratory muscles contract, causing the airways to narrow and constrict. This contraction is facilitated by a neurotransmitter called acetylcholine, which is released into the synaptic cleft
