PARATHYROID GLANDS 637 



of systematic studies must still be made in this field before any satisfactory 

 conclusions can be reached. 



Metabolism of Fats and Lipoids in Tetany 



Aside from (1) the observations of increased total metabolism in tetany 

 and (2) the observations on the occurrence of acidosis in tetany, I can find 

 but little in the literature referring to the fat metabolism in this disease. 

 The same may be said of the metabolism of lipoids in tetany. 



Mineral Metabolism in Tetany 



On the subject of the metabolism of mineral substances in tetany there 

 is now a considerable literature. It would be tedious to pursue the studies 

 that have been made in their minute and intricate details, but the essential 

 points can quickly be summarized. The majority of the metabolic re- 

 searches in tetany have dealt with (1) the disturbances of the acid base 

 equilibrium and (2) the disturbances of kation balance that occur, notably 

 with the deficiency, in the content of the blood and tissues, of calcium and 

 magnesium ions (nerve sedatives), and with the coincident preponderance 

 of sodium ions (nerve irritants). In infants the tendency to retention of 

 water in the so-called "water babies," which are especially prone to exhibit 

 the tetany syndrome, has raised, too, the general question of the behavior 

 of water metabolism in parathyroid insufficiency. Though the kations in 

 tetany have received much attention from investigators of metabolism, 

 there has as yet been but little work done upon the behavior of anions in 

 this disease, nor has the important matter of the interrelationships of 

 electrolytes to colloids in tetany been the subject of the study that it merits. 



Calcium and Magnesium. Sabbatani (1901) observed that calcium 

 salts are antagonistic in their effects on the animal organism to sodium 

 citrate, and made experiments that proved, by applying the salts directly 

 to the surface of the brain, that these effects concern especially the irrita- 

 bility of the nervous system. Calcium chlorid solutions reduce the mechan- 

 ical and electrical excitability immediately, whereas sodium citrate and 

 sodium oxalate have an opposite effect. The latter salts greatly increase 

 the excitability of the nervous system, so that the stimuli necessary to pro- 

 duce muscular movements are markedly decreased. Calcium applied after 

 sodium will neutralize the effects of the latter. As an inference from his 

 experiments, Sabbatani suggested that calcium might be useful in the treat- 

 ment of epilepsy. 



J. Loeb, in 1902, showed that the injection into the animal body of any 

 salt that precipitates calcium results in the development of muscular 

 twitchings. He suggested that, in disease abnormal conditions, in which 

 an increase of such acids in the circulation could diminish the amount of 



