Which type of receptor is stimulated in smooth muscle by muscarinic action?

Muscarinic action primarily involves the stimulation of cholinergic receptors, specifically the muscarinic subtype which is a type of acetylcholine receptor. When acetylcholine binds to these receptors, it induces a parasympathetic response in smooth muscle, leading to various physiological effects such as contraction of smooth muscle in organs like the gastrointestinal tract and bronchi.

Cholinergic receptors are further divided into two main types: nicotinic and muscarinic. Muscarinic receptors are located on the effector cells of the parasympathetic nervous system, and their stimulation is responsible for promoting the effects associated with this system, such as stimulation of glandular secretions and modulation of smooth muscle contraction.

Understanding this distinction is crucial for understanding pharmacological interventions targeting these pathways. For instance, drugs that activate muscarinic receptors can be used to treat conditions like asthma or bradycardia by enhancing the effects of acetylcholine on smooth muscle.