VIP-sensitive adenylate cyclase, guanylate cyclase, muscarinic receptors, choline acetyltransferase and acetylcholinesterase, in brain tissue afflicted by Alzheimer's disease/senile dementia of the Alzheimer type
Biochemical parameters were determined in autopsy material from several brain regions of thirteen patients with Alzheimer's disease/senile dementia of Alzheimer type (AD/SDAT) (mean age 75 years) and from brains of ten age-matched controls (mean age 76 years). Choline acetyltransferase specific activity was significantly lower in the nucleus caudatus, putamen, left thalamus, hippocampus and the cortex from gyrus hippocampus and the temporal lobe in AD/SDAT, acetylcholinesterase specific activity was significantly lower in the hippocampus, parietal and left frontal lobe in AD/SDAT samples than in corresponding samples from aged-matched controls. A compensatory increase of muscarinic receptors was found in the nucleus caudatus and left frontal lobe samples in AD/SDAT. Guanylate cyclase activity was not significantly altered in AD/SDAT in the brain regions examined. The basal, non-stimulated activity of adenylate cyclase was significantly (p less than 0.05) elevated in hippocampus samples from AD/SDAT patients and the enzyme activity stimulated by the vasoactive intestinal polypeptide VIP (2 microM) or forskolin (10 microM) was also elevated in AD/SDAT although not significantly.