SELECTIVE ALTERATIONS OF HIGH-AFFINITY [H-3] FORSKOLIN BINDING-SITES IN ALZHEIMERS-DISEASE - A QUANTITATIVE AUTORADIOGRAPHIC STUDY

Quantitative autoradiographic analysis of high affinity [3H]forskin binding sites was carried out in postmortem brains from front normal controls and patients dying with Alzheimer's disease. Choline acetyltransferase (ChAT) activity and senile plaque formation were also quantified. [3H]Forskolin binding was markedly reduced in all layers of middle frontal gyrus in the Alzheimer brains and the deficit correlated with the deficit in ChAT activity in this area. In the hippocampal region [3H]forskolin binding was no different in the Alzheimer brains compared to controls, although ChAT activity was significantly reduced. There was an inconsistent reduction in [3H]forskolin binding in all layers of middle temporal gyrus which did not correlate with the cholinergic deficit. Significant senile plaque formation was observed in all 3 brain regions examined and [3H]forskolin binding did not correlate wih plaque formation in any brain region. Thus, while all 3 brain regions were affected by the pathological correlates of Alzheimer's disease, [3H]forskolin binding was consistently reduced only in frontal cortex. © 1990.