Dietary induced changes in catecholamine metabolites in rat urine.

The influence of dietary conditions on the excretion of catecholamine metabolites has been investigated in rats. Four groups of rats were nourished over several days, with the usual cereal rat chow (A) or a synthetic complete food (B) or 15% milk (C) or 12% sucrose solution (D). Interference from cereal-rich diet was observed on most metabolites: dopamine (DA), 3-O-methyldopamine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC), norepinephrine (NE) and epinephrine (E). The cereal-induced interference was the highest for conjugated DA metabolites. Sucrose diet suppressed the chemical dietary interferences on DA metabolites but induced sympathetic hyperactivity, together with sustained changes in lipid metabolism, as previously observed in sucrose overfeeding. Milk diet induced too catecholamine release but did not reduce dietary interference on DA and 3-MT. From these results, we conclude that the synthetic cereal-free meal B is convenient in studies including most catecholamine metabolites, except for conjugated DOPAC. In the latter case, sucrose diet proofs more appropriate, provided it is used over a short period.