THE THYROID APPARATUS 2Q 



H. Wiener found that, after removal of the inferior cervical 

 ganglion, there was a decrease in the cell-mass, together with an 

 increase in the thyroglobin contents, of the thyroid gland upon 

 the same side. The resection of the fifth and sixth spinal nerves 

 caused a reduction in the weight of the gland, unaccompanied, 

 however, by a decrease in the amount of thyroglobin. Wiener 

 concludes that the rami communicantes of these spinal nerves 

 are the roots of the sympathetic nerves of the gland ; though they 

 convey only trophic impulses, the secretory fibres having another 

 origin. 



CHEMISTRY. 



The earlier investigators (Kiihne, Oicltmann, Bubnow, 

 Gurlay, Morkuton, Notion, Drechsel, Hutchison) showed that, 

 among the chemical constituents of the thyroid gland are the 

 albuminoids both albumins and nucleoproteids containing 

 phosphorus albumose, leucin, xanthin, hypoxanthin, paralactic 

 acid, and succinic acicl. Of the inorganic substances, it contains 

 sodium chloride and oxalate of calcium. 



E. Baumann showed, in 1895, tnat the normal thyroid gland 

 contains large quantities of iodine in organic combination. It 

 was suggested by Kocher, even earlier, that the favourable effects 

 of the iodine preparations in goitre might be due to the fact 

 that iodine is a normal constituent of the thyroid gland. 



The amount of iodine present in the normal gland of man 

 and animals is 0.3-0.9 mg. to i grm. of the dried substance. 

 The entire organ contains 2-9 mg., or, according to Aschbacher, 

 an average of 6.48 mg. The thyroid gland of the foetus and of 

 the new-born infant contains no iodine, and it appears from this 

 that iodine is introduced into the organism with the food and 

 is stored in the thyroid gland. In children the amount of iodine 

 in the gland is less than in adults; according to Jolin, from i-io 

 years, it is 0.145 mg. According to Aschbacher, the average 

 up to 25 years is 2.43 mg. ; from 25-30 years, it is 8.98 mg. ; and 

 over 50 years of age it is 4.6 mg. Among animals, the thyroid of 

 herbivore contains a high percentage of iodine; that of 

 omnivorag is low; while the lowest percentage of all is contained 

 in the thyroid of carnivore, from which iodine may even be 

 absent altogether. 



The amount of iodine present in the thyroid may be taken 

 as a measure of the amount of iodine taken into the economy, 

 whether in food or as a medicament. According to Jolin, who 

 gives the average amount of iodine in the normal human thyroid 

 as 8.5 mg. the amount increases under iodine treatment to 15.6 mg. 

 Baumann states that the proportion of iodine is lowest in localities 

 where goitre is endemic such as Freiburg while the gland 

 weighs very heavily. In localities which are free from goitre 

 (Hamburg, Berlin) the opposite holds good, the weight of the 



