44 GLANDS IN HEALTH AND DISEASE 



sudden involuntary contractions of the muscles 

 and extremities. "The fits are sometimes frequent, 

 but more often occur at long intervals." The res- 

 piratory tract, the heart, and the body temperature 

 are also affected. The illness is very often pro- 

 longed, and often terminates fatally. There is a 

 loss in weight, indicating a disturbed metabolism. 

 The presumption that the metabolism of bone, and 

 particularly that relating to calcium, is affected, 

 has experimental support, in that the administra- 

 tion of calcium sometimes relieves the sufferer. 



That tetany is the result of the absence of the 

 parathyroids is clear enough when we consider 

 that the administration of parathyroid extract 

 relieves the patient, at least temporarily. You see, 

 we are here dealing with a case of hypo-parathy- 

 roidism, just as in cretinism and in myxedema we 

 dealt with instances of hypo-thyroidism ; and just 

 as the thyroid secretes a specific hormone the ab- 

 sence of which gives rise to cretinism in the child 

 and myxedema in the adult, so the parathyroid 

 secretes a hormone the absence of which gives rise 

 to tetany. Notice that the most important piece 

 of evidence for this view is that in both cases the 

 symptoms disappear upon the administration of 

 the extract of the appropriate gland. 1 



*The results with parathyroid extracts are more conflicting 

 than those with thyroid ones. A safer position to take would be 

 to say that the symptoms of tetany can be removed by "grafting" 

 the gland, rather than by administering an extract of the gland. 



