Effect of chronic low potassium on K+ uptake rate in myocardium and skeletal muscle of rabbits / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of chronic low potassium on K+uptake rate in the my?ocardium and skeletal muscle of rabbits. Methods Thirty?two adult male rabbits, aged 12-14 weeks, weighing 2?0-2?7 kg, were randomly divided into 4 groups ( n=8 each) using a random number tablenormal feeding group ( group N) , low potassium feeding group ( group L) , potassium supplementation con?trol group ( group SC ) and potassium supplementation experimental group ( group SE ) . N and SC groups were given a normal diet only, and L and SE groups were fed with a low potassium diet for 15 days. Potassi?um chloride ( KCl) 0?5 mol∕L was then infused intravenously at the initial rate of 60 μmol·kg-1 ·min-1 in SE and SC groups. Blood samples were obtained from the central artery of the left ear every 5 min for meas?urement of plasma K+ concentrations. The infusion rat of KCl was then adjusted until the plasma K+concen?tration reached 5?5 mmol∕L and maintained at this level for 1 h, and then infusion was stopped. The total volume of KCl infused was recorded. The hearts and soleus muscle of animals were excised for determination of K+content. K+uptake and uptake rate were calculated. Results Compared with N group, the plasma K+concentration, and K+content in the myocardium and soleus muscle were significantly decreased in group L ( P<0?05) . Compared with SC group, the total volume of KCl infused, and K+uptake and uptake rate in the myocardium and soleus muscle were significantly increased in group SE ( P<0?05) . Conclusion Chro?nic hypokalaemia can increase K+ uptake rate in the myocardium and skeletal muscle of rabbits.