[Effect of chronic ethanol consumption on the thyroxine hydroxylase activity of various brain structures in rats].

The effect of chronic (8-week long) 5 percent-ethanol consumption on the activity of tyrosine hydroxylase on the rat brain hypothalamus, striatum and midbrain was studied. In rats with strong ethanol prefence the enzyme activity was found to increase by 65-86 percent in the hypothalamus and to diminish by 52-68 percent and 29-68 percent in the midbrain and striatum, respectively. In rats with weak ethanol preference the enzyme activity in the brain striatum and midbrain remained unchanged, while in the hypothalamus it decreased by 25-40 percent. Chronic ethanol consumption had no effect on the inhibition of the enzyme activity neither by dopamine (8.0 X10(-4)M), nor tyrosine (in an inhibitory concentration of 3.7X(10(-4)M).