Changes in density of muscarinic cholinergic receptor by adrenergic denervation with guanethidine

The effects of chronic adrenergic denervation with guanethidine on muscarinic cholinergic receptors (mAChR) were investigated by binding of L-3H-quinuclidinyl benzilate (3H-QNB). Guanethidine treatment decreased the amount of mAChR from 102 to 87 fmoles/mg protein in the heart and from 444 to 388 fmoles/mg protein in the small intestine, but increased it from 223 to 282 fmoles/mg protein in the vas deferens, without changes in its characteristics. These findings suggested that adrenergic innervation has different influences on the mAChR population in different tissues.