Metabolic Reactions to Acidosis Produced by Ammonium Chloride

Abstract

Acidosis is so frequently put forward as the underlying pathological condition in such a variety of disorders that it is important to appreciate what actually are the metabolic manifestations of the acidotic state. Clinically one seldom if ever has an opportunity of studying acidosis uncomplicated by some such other factor as inanition or toxaemia. It is therefore advisable in an investigation of the metabolic reactions to a disturbance in acid-base equilibrium to have these secondary factors as far as possible excluded. This can only be done when the acidosis is induced in a healthy individual with the minimal amount of upset especially as regards food-intake, and such a condition is most nearly attained in the acidosis produced by the ingestion of ammonium chloride. Haldane' was the first to show that ammonium chloride taken in large amounts led to a marked acidosis owing to its ammonium moiety being converted to urea. Since then many papers have been published dealing with changes following the administration of this substance.The present research was undertaken primarily with the object of studying the changes in mineral metabolism during acidosis and, if possible, of correlating these changes with other metabolic phenomena. Most workers are agreed that there is an increased output of lime in the urine during acidosis. The effect on the faecal excretion of lime and the influence of the acidotic state on phosphorus metabolism have not, however, been clearly determined. Steenbock, Nelson and Hart2 have pointed out the detrimental effect of acid-forming diets on calcium retention and calcification in animals. Sawyer, Bauman and Stevens3 found an increased urinary output of calcium and phosphorus in two children during a period of high fat intake: in only one, however, was there an increase in the fwecal amounts of these substances, while in the other there was a decrease. In a study of acid and base-forming diets in adult women Bogert and Kirkpatrick4 did not obtain a constant change in the amount of feecal calcium during the period ofLcid-forming diet although the urinary lime was always increased.

Factors Influencing the Urinary Excretion of Calcium. I. In Normal Persons1

“…Values for urine Ca x 100 were inintake Ca creased far above the normal maximum. Ammonium chloride increased the urine calcium excretion of children (27) and adults (56) above the normal maximum. Ingestion of an acid-ash diet by adults (56), although less effective than NH4C1, did increase the urine calcium from values near the mean to values near the normal maximum level of excretion.…”

“…All data were taken from the literature (27,(56)(57)(58), and in every study each subject served as his own control. The calcium intake was nearly constant in all studies except one (27) in which the experimental diet contained less calcium than the control. Ingestion of ketogenic diet (fatty acid: glucose = 2.6) by children resulted in the most marked increase in urinary calcium.…”