Plasma catecholamines in acute magnesium deficiency in weanling rats.

A controlled study was conducted to quantitate plasma catecholamines in magnesium-deficient weanling rats experiencing the seizure-shock episode. Eighty-four male Sprague-Dawley rats each weighing 35.6 +/- 0.

Radioenzymatic assay of DOPA (3,4-dihydroxyphenylalanine).

We modified the single-isotope radioenzymatic assay for catecholamines [Life Sci. 21, 625 (1977)] to assay 3, 4-dihydroxyphenylalanine (DOPA). DOPA decarboxylase is used to convert DOPA to dopamine, which concurrently is converted to [3H]-3-O-methyldopamine in the presence of catechol-O-methyltransferase and [methyl-3H]-S-adenosylmethionine and assayed radioenzymatically.