The retrograde transport of receptor-bound opiate was markedly enhanced in the vagus nerves of rats housed for 25 days in an atmosphere of ethanol vapor. This increase disappeared after 8 days of withdrawal as did the animal preference for ethanol. In contrast, the axonal transport of muscarinic receptors in sciatic nerves was slightly reduced. This provides more evidence for the idea that chronic alcoholization and morphine addiction share a common denominator and that the retrograde transport of receptor-bound signal molecules represents a link between the synapses and the cell-body of neurones.