The Parathyroids:—tetania Parathyreopriva: Its Nature, Cause, and Relations to Idiopathic Tetany. Part I.: Introduction, General Methods, and Symptoms

Abstract

1. Idiopathic tetany and the various theories as regards its etiology are considered. 2. The previous work upon experimental tetany is dealt with in the three periods— (a) before the recognition of the possible significance of the parathyroid; (b) while the distinction between the thyroids and parathyroids was still doubtful; (c) after the direct implication of the parathyroids in the production of the symptoms had been established. The evidence that the condition is a true tetania parathyreopriva is considered to be conclusive. 3. The method of removing the parathyroids is considered, and the impossibility of getting rid of the internal parathyroids with certainty by any operation but complete thyroparathyroidectomy is indicated. The existence of supplementary parathyroid tissue in about 50 per cent. of cats and in probably about 5 per cent. of dogs is shown to explain the absence of symptoms in some cases of thyroparathyroidectomy. 4. The symptoms of tetania parathyreopriva are considered under the following heads:— I. Their protean character. V. Tremors and fibrillar tremblings. II. Depression. VI. Jerkings. III. Emaciation. VII. Convulsions. IV. Spasticity. VIII. Disturbances of balance. 5. Some of the factors modifying the character and onset of the symptoms are briefly considered:— (a) The nature of the food. (c) Rickets. (b) Age. (d) Pregnancy and lactation.

The Function of Creatine in Muscular Contraction.

“…The strongly basic properties of these substances, their reported occurrence in muscle, and in normal human urine, and their reported increase there during abnormal muscular activity (25), suggested that creatine might be undergoing a c-hange into one of these two substances. At the same time, there were a number of serious objections to this view.…”

The chronaxie in tetany

“…Recent years have produced much work, notably that of Noel Paton and Findlay (2) and more recently of Frank Stern and Nathmann(3) and Gy6rgy and Vollmer4 on the experimental production in animals of the symptoms of tetany by parathyreoid removal and by the injection of guanidin and di-methyl guanidin salts. A lowering of the galvanic threshold in a manner strictly similar to that seen in idiopathic tetany is shown to be a constant phenomenon in such conditions experimentally produced.…”

“…To determine the chronaxie by condenser discharges Lapicque proceeds as follows: (1) the rheobase is found by determining the minimal current which will excite if allowed to run continuously (i.e. for more than half a second); (2) the voltage required for the rheobase is doubled, and a series of condensers is charged to this value. These condensers are now discharged through the tissue and the smallest capacity which will just excite is determined.…”

Cholin in the blood after parathyreoidectomy

“…W. F. KoCH(1) found in the urine of parathyreoidectomiised dogs a number of toxic bases, including guanidin and dimethyl-guanidin, to which he ascribed the symptoms. Noel Paton, Findlay and Watson, in conjunction with Burns and Sharp e (2) independently arrived at the conclusion that guanidin or its methyl derivatives are the toxic agents in tetania parathyreopriva and in idiopathic tetany. B ie d (3,p.…”