Effect of cimetidine, ranitidine and famotidine on norepinephrine, dopamine and serotonin contents in different brain areas of mouse

ABSTRACT

The acute and subacute effects of histamine [H2] receptor antagonists [cimetidine, ranitidine and famotidine] on norepinephrine [NE], dopamine [DA] and 5-hydroxytryptamine [5-HT] contents have been studied in different brain areas of mouse; namely, cerebral cortex, thalamus and hypothalamus, midbrain as well as the area of medulla, pons and cerebellum. The doses used were equivalent to the human therapeutic dosage. The results revealed that cimetidine [50, 100 mg/kg], ranitidine [19, 38 mg/kg] and famotidine [2.5, 5 mg/kg] caused significant increase in norepinephrine and dopamine contents in the most of the examined brain areas after single and twice daily 15 days administration. It was shown that 50 mg/kg cimetidine decreased 5-HT content in thalamus and hypothalamus after 15-days administration. Increasing the dose to 100 mg/kg resulted into an increase in 5-HT content in the area of thalamus and hypothalamus and that of midbrain respectively after acute or subacute administration. It is probable that the changes in brain monoamines content observed may play a role in CNS adverse effect of H2-receptor antagonists