Potassium content of some Nigerian plant foods and effects of daily consumption on blood pressure and pressor responses in rats

Abstract

The study set out to assay the potassium content of ten locally eaten plant foods and to determine the possible effects of daily consumption of the foods on blood pressure and pressor responses in rats. The potassium contents of nine fruits and carrot were determined by flame atomic absorption spectrophotometry. The two with the highest amounts of potassium were fed to rats at a dose 5 g/day for 28 days. Tap water (2 ml/day) and potassium citrate (25 mg/kg) for 28 days served as negative and positive controls respectively. Blood pressure and pressor responses to noradrenaline, verapamil and sodium nitroprusside were measured by invasive method. The potassium concentration varied in all the foods with carrot and plantain having the highest amount of potassium (0.42 ± 0.14 and 0.36 ± 0.10 % w/w respectively). Carrot, plantain and potassium citrate did not significantly lower blood pressure. The pressor responses to 10 μg/kg noradrenaline were significantly attenuated in the carrot (P < 0.02) and plantain (P < 0.05) fed rats compared to controls. Also, carrot significantly (P < 0.05) augmented blood pressure decreases to sodium nitroprusside and verapamil. The study shows that carrot and plantain may be helpful in preventing acute blood pressure increases while carrot may augment the antihypertensive effects of some drugs.