Muscarinic receptors on human eccrine sweat gland in aging and Alzheimerʹs disease

Age and Alzheimerʹs disease-related changes have been reported in the peripheral cholinergic system controlling sweating. We present (1) evidence of a high affinity muscarinic receptor localized on human eccrine sweat gland and (2) muscarinic receptor concentrations on eccrine gland samples from 22 patients with probable Alzheimerʹs disease of various degrees of dementia, 8 age-matched controls, and 11 young controls. Muscarinic receptors were measured using autoradiography with 3H-NMS as ligand. We found no evidence of changes related to aging or Alzheimerʹs disease in the overall concentration of receptors or in the amount of gland showing binding. Nor was there any correlation between the degree of dementia as measured by the Global Deterioration Scale or the Mini-Mental State Exam and 3H-NMS binding. In conclusion, we find no evidence that previously reported sweat gland functional changes associated with aging and Alzheimerʹs disease are reflected in changes in eccrine gland muscarinic receptor density.