Potential types of response of the parasympathetic denervated human parotid gland to cholinergic ligands.

Investigation of functioning of human parotid salivatory glands, both normal and postdenervated, has demonstrated the presence of 5 main types of salivatory responses to cholinergic agonists and antagonists. Existence of various types of response has indicated the presence of different subpopulations of M-cholinergic structures that interact differently with the agents of cholinergic induction and blockade. Two subtypes function in the norm and they are conditioned by the presence of a double regulation; nervous and humeral. Three additional potential subtypes of response have been revealed only under conditions produced by various degrees of the gland's denervation. The data obtained relate to the nature of multireceptors or receptor states within the M-cholinergic system.