380 INOSITOLS 



ably is relatively poorly absorbed, and it is probable that the effect on 

 motility of the gastrointestinal tract is due to an irritating action. In this 

 connection, the observations of Clark and Geissman^^ that inositol does not 

 potentiate the action of epinephrine on an isolated smooth muscle prepara- 

 tion are of interest. Torda and Wolffs* found that inositol increases the 

 sensitivity of striated muscle of the frog to acetylcholine, but data on the 

 smooth muscle of the gastrointestinal tract are not available. 



C. THYROID 



The presence of inositol in the thyroid gland was demonstrated by Tam- 

 bach^^ and Meyer. ^^ However, few data on the effect of inositol on thyroid 

 function are available. Abelin^^ produced toxic symptoms in rats by the 

 administration of 100 mg. of thyroglobin daily for 1.5 months, with re- 

 duction in body weight and in muscle creatine and increase in rate of 

 respiration. The daily parenteral administration of 50 to 100 mg. of panto- 

 thenic acid prevented the occurrence of toxic symptoms. Inositol and py- 

 ridoxine had similar effects. Handler and Follis^^ observed that a decreased 

 level of thyroid activity induced by thyroidectomy or by thiouracil or p- 

 aminobenzoic acid feeding prevented or retarded the development of he- 

 patic necrosis or fibrosis associated with choline and cystine deficiencies 

 in the rat and that thyroid administration hastened the death of cystine- 

 deficient rats. Inositol, as well as sulfasuxidine and taurine, prevented the 

 development of hepatic cirrhosis in animals on a diet deficient in choline. 

 This effect of inositol, however, was not due to lipotropic action or anti- 

 thyroid activity, since inositol did not reduce the fat content of the fatty 

 livers, nor did it produce morphological changes in the thyroid. 



D. NEUROMUSCULAR SYSTEM 



Inositol is a constituent of striated muscle" • 21 . 24 , 28 g^^-^^j ^f ^j^g spinal 

 cord and brain. -^ Investigations on the pharmacologic action of inositol 

 on the brain apparently have not been done, but Lecoq et al.^° in their 

 studies on the effect of a number of compounds on nerve chronaxia in rats 

 observed that inositol caused an increase in nerve chronaxia. Moreover, 

 inositol had no effect on the increase in chronaxia after repeated adminis- 



23 W. G. Clark and T. A. Geissraan, /. Pharmacol. Exptl. Therap. 95, 363 (1949). 



24 C. Torda and H. G. Wolff, Am. J. Physiol. 145, 608 (1945-1946). 

 2SR. Tambach, Pharm. Zentralhalle 37, 167 (1896). 



26 I. Abelin, Experientia 1, 231 (1945). 



27 P. Handler and R. H. Follis, Jr., J. Nutrition 35, 669 (1948). 



28 J. Scherer, Ann. Chem. Justus Liebigs 73, 322 (1850). 



29 J. Folch and D. W. Woolley, J. Biol. Chem. 142, 963 (1942). 



30 R. Lecoq, P. Chauchard, and H. Mazoud, Bull. soc. chim. hiol. 30, 296 (1948); 

 Compt. rend. 227, 307 (1948); Compt. rend. soc. hiol. 142, 428 (1948). 



