Cerebral catecholamine depletion in mice withdrawn from repeated morphine treatment and development of tolerance to the enhancing effect of morphine on noradrenaline depletion.

The effect of repeated morphine administration on the alpha-methyl-rho-tyrosine (alpha M rho T)-induced depletion of catecholamines was investigated in various brain areas of mice withdrawn for 1, 2, 3 and 7 days from 5-day morphine treatment. In addition, to clarify the development of tolerance, the effect of acute morphine administration on alpha M rho T-induced depletion of catecholamines was studied in these selected brain areas of mice withdrawn from repeated morphine treatment. Dopamine depletion was significantly (P