The effect of clonidine withdrawal on total 3-methoxy-4-hydroxyphenylglycol in the rat brain.

The effect of clonidine withdrawal on the brain norepinephrine system was studied in the rat. Clonidine suppresses brain total 3-methoxy-4-hydroxyphenylglycol (MHPG) significantly and no tolerance to this effect was observed up to 21 days. Cessation of clonidine treatment resulted in an elevation in the level of brain total MHPG. The suitability of the clonidine withdrawal syndrome as a model of bipolar depression is discussed.