944 INFLUENCE OF DUCTLESS GLANDS ON METABOLISM. 
an increased production of heat. This increase of carbonic acid does not 
take place immediately, but only comes on after a certain period of 
time ; the temperature of the body being in the meanwhile maintained 
normal by those physical changes which occur in the circulation, and 
which allow the quantity of blood brought to the skin, and the amount 
of heat thereby lost from the general surface of the body, to be varied. 
Now, it is precisely these vasomotor changes which appear to be lack- 
ing after removal of the thyroid ; for the production of carbon dioxide 
becomes almost immediately increased by exposing thyroidectomised 
animals to a low temperature. Cardiac palpitations with increased 
Fig. 85. — Effect iu the dog upon the blood pressure of the intravenous injection of decoc- 
tion of thyroid. Time in seconds. The line above the time tracing is the abscissa 
of the mercurial manometer. 
pulse frequency, often accompanied by a feeling of giddiness, may 
sometimes be produced by large doses of fresh thyroid ; after a time 
glycosuria and increase of urea appear. 1 Experiments upon the effect 
of thyroid feeding on metabolism have been made by various observers. 2 
Eichter 3 found in man no marked effect on nitrogenous metabolism, 
but Bleibtreu and Wendelstadt and also Eoos got a distinct increase 
of excreted nitrogen during thyroid feeding. Schondorff obtained an 
increased excretion of nitrogen during the first eight days (in dog) ; 
after that, X -balance was maintained, while the body-fat was greatly 
diminished in amount. The sodium chloride and phosphoric acid were 
also somewhat increased. Bettmann 4 states that thyroid feeding tends 
to produce "alimentary glycosuria" (see p. 881). 
1 Georgiewsky, Centralbl. f. d. mcd. TFissensch., Berlin, 1895, Bd. xxvii. 
2 Xapier, Lancet, London, 1893, vol. ii. p. S05 ; Xevmehren, Deutsche mcd. Wch nschr. , Leipzig, 
1893, Xo. li ; Dening, Miinchen. tried. IVchnschr., 1895, S. 464 ; Bleibtreu and Wendelstadt, 
Deutsche med. IVchnschr., Leipzig, 1895, S. 346; Mediger, Diss., Greifswald, 1895 
(abstract in Centralbl. f. Nervenh. u. Psychiat., Coblenz u. Leipzig, Bd. xviii. S. 289) ; 
Lanz, Deutsche med. IVchnschr., Leipzig, 1895, S. 597 ; Irsal, Yas, and Gara, ibid., 1896, 
Bd. xxii. S. 439 ; SchondorrT, Arch. /. d. ges. Physiol., Bonn, 1896, Bd. lxiii. S. 423; 
Gluzinski and Lemberger, Centralbl. f. inncrcMed., Leipzig, Bd. xviii. S. 90 ; Koos, Ztschr. 
f. physiol. Chem., Strassburg, 1895, 'Bd. xxi. S. 19; and 1896, Bd. xxii. S. 18; Giirber, 
Sitzungsb. d. phys.-med. Gesellsch. zu TViirzburg, 1896, S. 101. 
s Centralbl. f. innere Med., Leipzig, 1S96, S. 65. 
4 Perl. Hin'. IVchnschr., 1897, S. 518. 
