[Effect of L-dihydroxyphenylalanine on rat behavior and on catecholamine metabolism of the brain in rats with different degrees of emotional-behavioral reactivity].

The effect of L-DOPA in combination with benserazide (Madopar), administered intraperitoneally on the rat behaviour and L-DOPA, DA, NE, DOPAC content in rat brain structures was studied depending on the level of the animals' emotional-behavioural reactivity. The results indicate that L-DOPA metabolism in striatum, n. accumbens and hypothalamus in intact animals with high emotional reactivity was the greatest. Administration of Madopar (50 mg/kg) induced significant behavioural disturbances in animals with less emotional-behavioural response patterns. In contrast, 125 mg/kg Madopar completely abolished individual differences in the rats' behaviour and DA, but not L-DOPA and DOPAC content. The correlation between behavioural and biochemical differences in two groups of animals is discussed in view of distinctions in L-DOPA and DA compartmentation process.