ABSTRACT
Objective To investigate the possible effect of citrate on electrolyte metabolism in healthy people with different genders and races and provide a reference for the possible clinical interventions.Methods A cross over,placebo-controlled study was conducted in 22 age-matched Chinese(11 males and 11 females)and 10 male Caucasian volunteers after informed consents were obtained.Volunteers received of saline solution,separated by a wash-out period of two to three weeks.Serial blood and urine samples were collected during the observation period and analyzed for the selective biochemical parameters.Results Comparable basal levels of serum albumin[male(43.05±1.81)g/L vs female(42.26±2.67)g/L]and serum ionized calcium[male(1.27±0.04)mmol/L vs female(1.26±0.04)mmol/L]were observed between different genders of Chinese volunteers.However,citrate intervention led to more pronounced decrease of ionized calcium level in Chinese females compared to Chinese males[-28.68%(-20.00%--35.2%)vs-23.84%(-16.53%--29.32%),t=3.19,P ＜ 0.01].There was no differences of the levels of serum inorganic phosphate[-18.81%(-3.16%--25.09%)vs-19.23%(-1.22%--32.16%),t=0.36,P＞0.05]and albumin[-0.32%(3.27%--7.60%)vs 1.88%(6.03%--9.31%),t=0.47,P＞0.05].Independent of gender,citrate intervention resulted in an increased excretion of urine calcium in Chinese volunteers[before 0.34(0.09-0.87)vs after 0.96(0.18-1.47),t=6.66,P ＜0.01].Compared to Caucasian males,Chinese males has a higher basal level of serum ionized calcium [(1.27±0.04)mmol/L vs(1.22±0.02)mmol/L,t=3.7,P ＜0.01]and larger amplitude basal rhythm in serum albumin level[-11.72%(-5.70%--14.21%)vs-1.74%(2.43%--7.68%),t=7.43,P ＜ 0.01].Application of citrate resulted in comparable changes of serum ionized calcium [-23.84%(-16.53%--29.32%)vs-21.95%(-18.31%--30.92%)],phosphate[-19.23%(4.65%--32.16%)vs-12.68%(0.68%--42.19%)],albumin[-0.32%(1.05%--7.60%)vs-1.39%(1.87%--7.26%)]and urine calcium excretion[237.70%(11.8%-935%)vs 234.37%(5.45%-504.00%)]between Chinese and Caucasian males(t=0.32,0.03,0.25 and 0.04 respectively,P＞0.05).Serum levels of magnesium were not influenced in all volunteers during two interventions.Conclusions Independent of race and gender,the invention of citrate results in comparable changes of serum magnesium,inorganic phosphate and albumin.The effect of citrate on ionized calcium levels between genders implicates a higher risk for hypocalcemic reactions in females compared to males undergoing automatic apheresis procedures.