Key result
Silabenzhexol was highly selective for ileal muscarinic receptors (~50-fold), whereas AF-DX 116 was selective for atrial receptors (~6-fold), supporting the existence of distinct receptor subtypes.
Population
In vitro models of atrial and ileal muscarinic receptors
Design
Preclinical
Authors
Loading...
Supports muscarinic subtype heterogeneity in isolated tissues; leaves open clinical translation of selective antagonists.
The study supports the existence of distinct ileal and atrial muscarinic receptor subtypes based on differential antagonist affinities, though compounds like dicyclomine have limited utility for receptor classification due to non-competitive behavior.
Eglen et al. (1987) studied this question. Muscarinic agonists and antagonists (e.g., silabenzhexol, AF-DX 116) was evaluated on Affinity and selectivity at atrial vs ileal muscarinic receptors. Silabenzhexol was highly selective for ileal muscarinic receptors (~50-fold), whereas AF-DX 116 was selective for atrial receptors (~6-fold), supporting the existence of distinct receptor subtypes.
Synapse has enriched one closely related paper. Consider it for comparative context: