AUTORADIOGRAPHIC DEMONSTRATION OF AN INCREASE IN MUSCARINIC CHOLINERGIC RECEPTORS IN CEREBELLAR GRANULE CELLS TREATED WITH TETRAHYDROAMINOACRIDINE

The neurotrophic and neurosurviving effects of 9-amino-1,2,3,4-tetrahydroacridine (THA), a putative antidementia agent, were studied in cultured granule cells using biochemical and morphological methods. The addition of 30 muM THA to cultures grown in 15 mM K+-containing media markedly increased cell survival and enhanced [H-3]N-methylscopolamine binding to muscarinic cholinergic receptors (mAChRs). Furthermore, receptor autoradiographic studies revealed that neuronal cells were labelled over both cell bodies and fibers by the [H-3]receptor ligand. These observations provide direct evidence that THA promotes the expression of mAChR binding sites in differentiating cerebellar granule cells.