1. Akera, T., Brody, T.: The addiction cycle to narcotics in the rat and its relation to catecholamines. Biochem. Pharmacol. 17, 675?688 (1968)
2. Algeri, S., Costa, E.: Physical dependence on morphine fails to increase serotonin turnover rate in rat brain. Biochem. Pharmacol. 20, 877?884 (1971)
3. Buxbaum, D. M., Yarbrough, G. G., Carter, M. E.: Biogenic amines and narcotic effects I. Modification of morphine-induced analgesia and motor activity after alteration of cerebral amine levels. J. Pharmacol. exp. Ther. 185, 317?327 (1973)
4. Cheney, D. L., Goldstein, A.: The effect of p-chlorophenylalanine on opiate induced running, analgesia, tolerance and physical dependence in mice. J. Pharmacol. exp. Ther. 177, 309?315 (1971)
5. Cochin, J., Kornetsky, C.: Development and loss of tolerance to morphine in the rat after single and multiple injections. J. Pharmacol. exp. Ther. 145, 1?10 (1964)