Regulation of Neuronal Nicotinic Receptors in Primary Cultures

Abstract

We used [3H]cytisine to characterize nicotinic cholinergic receptor binding sites in rat brain neurons grown in culture. Primary cells were obtained from several different areas of fetal rat brain at 18 days gestation and were kept in culture for up to 15 days. [3H] Cytisine binds with high affinity to primary cultures of neurons from cerebral cortex, hippocampus and striatum; but the highest binding (≈ 50 fmol/mg protein) was found in neurons from a region containing thalamus, midbrain and brainstem, which we refer to here as the TMB. Culturing cortical neurons in the presence of nicotine for 7 days increases the number of nicotinic receptor binding sites labeled by [3H]cytisine. Primary neuronal cultures should be useful as model systems for studies of subunit composition and molecular mechanisms involved in the regulation of neuronal nicotinic receptors.