Summary
The effect of dihydralazine on monoamine metabolism in the rat was investigated. Dihydralazine, 5 mg/kg i.v., reduced noradrenaline (NA) in the heart. After pretreatment with phenoxybenzamine an NA depletion was evident also in the brain. Dihydralazine did not affect the utilization of NA or dopamine in the brain as judged by the disappearance rates of these amines following synthesis inhibition byα-methyl-p-tyrosine. However, dihydralazine reduced the synthesis of monoamines as evidenced by a decreased accumulation of the monoamine precursor dihydroxyphenylalanine (and 5-hydroxytryptamine) subsequent to treatment with NSD 1015.
It is concluded that dihydralazine inhibits central tyrosine hydroxylase (and tryptophan hydroxylase) in the rat.
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Persson, B., Svensson, T.H. & Henning, M. Dihydalazine inhibits tyrosine hydroxylasein vivo in the rat. J. Neural Transmission 53, 109–116 (1982). https://doi.org/10.1007/BF01243402
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DOI: https://doi.org/10.1007/BF01243402