Muscarinic receptors on human eccrine sweat gland in aging and Alzheimer's disease

Age and Alzheimer's 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 Alzheimer's 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 Alzheimer's 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 Alzheimer's disease are reflected in changes in eccrine gland muscarinic receptor density.