Possible Interaction: Dextroamphetamine and Metyrosine

“Pretreatment with the tyrosine hydroxylase inhibitor, α-methyl-para-tyrosine , blocked the effects induced by l-DOPA, dopamine and dexamphetamine in a competitive way; the 3-methoxy-tyramine effect was blocked in a non-competitive way.”

“Pretreatment with α-methyl-p-tyrosine (100 mg/kg, 1 hr before) had only a slight depressant effect on startle but essentially eliminated augmentation of startle by either d-amphetamine (8 mg/kg) or l-amphetamine (32 mg/kg).”

“ α-Methyl tyrosine pretreatment blocked the effects of 1 but not 3 mg/kg of d-amphetamine in the withdrawn animals.”

“Whereas reserpine, onizes the effect of methylphenidate but not that antag of (+)-amphetamine, cc-methyltyrosine antagonizes the ctfect of (+)-amphetamine but not that of methyl*henidate.”

“The anorexia produced by (+)-amphetamine was antagonised by α-methyl-p-tyrosine methyl ester HC1 (40–160 mg/kg, i.p.)”

“Semi-quantitative … suggestion that u-methyltyrosine prevents … (+)-amphetamine (Weissman & Koe, 1965 ; Weissman, Koe & Tenen, 1966; Mennear & Rudzik, 1966; Dingell, Owens & others, 1967; Hanson, 1967), and the suggestion that (+)-amphetamine … delay the onset of the behavioural impairment that otherwise follows administration of a-methyltyrosine (Moore & Rech, 1967a ; Poschel & Ninteman, 1966).”

“We wish to confirm his observation and extend it to demonstrate that this antagonism of a-methyltyrosine by (+)-amphetamine is stimulus-dependent.”

“Weissman & … of a-methyltyrosine to prevent, or rapidly … normally seen after (+)-amphetamine by summarizing evidence : that the excitatory action of (+)-amphetamine is dependent upon the release of catecholamines to the … the availability of catecholamines for release is dependent upon maintenance of the functional pool ; that a-methyltyrosine compromises the”

“Hyperactivity was selectively reduced in isolated rats by chronic oral treatment with d-amphetamine , 5 mg/kg/24 h. It was also reduced 15 min after pretreatment with α-methyl-p-tyrosine 200 mg/kg.”

“In contrast, comparably sized excitatory effects of d-amphetamine were blocked by α-methyl-p-tyrosine and greatly enhanced by pretreatment with reserpine.”

“Consumption of the d-amphetamine solution was increased by injections of several doses of α-methyl-p-tyrosine (AMPT).”

“ α-Methyltyrosine antagonized the increased self-stimulation responding following administration of d-amphetamine (1 mg/kg) to reserpinized rats, while U-14624 did not.”