Muscarinic M3 receptors mediate secretion from sweat glands in the rat

We investigated a series of muscarinic antagonists for their ability to inhibit muscarinic-mediated secretions from salivary and sweat glands in the rat. Their potency in blocking saliva secretion was compatible with the inhibition of M3 receptors. A highly significant correlation was found between their potency in blocking secretion from both salivary and sweat glands. These results indicate that salivary and sweat glands possess the same muscarinic receptors which conform to the M3 subtype.