Saliva and sweat secretion in man during a one-hour calcium clamp

The effect of a 1-h calcium infusion, directly regulated to obtain and maintain a predetermined blood calcium level ('calcium clamp'), on the composition of parotid saliva, mixed saliva, and sweat was determined in healthy volunteers. An increase in amylase content of the parotid saliva under hypercalcaemic conditions was observed, but the 'calcium clamp' had no effect on flow rate, total and ionized calcium, sodium, potassium, and phosphate levels as well as pH in parotid and mixed saliva. The sweat calcium concentration was negatively correlated with sweat rate, in contrast to sodium and chloride concentrations. Increasing serum calcium levels did not affect ionic composition of the sweat and sweat flow rate.