X. PHARMACOLOGY 379 



Chevalier^^ perfused the rabbit's heart with inositol in concentrations of 

 0.05 and 0.1%. The lower concentration of inositol produced definite 

 acceleration and more forceful activity, but use of the larger amounts of 

 inositol was followed by gradual slowing of the heart and stoppage in 

 systole. Meyer^^ observed that, in the perfused rabbit's heart, inositol 

 concentrations of 0.01 and 0.02% produced a decrease in amplitude and 

 arrythmias. However, since the concentrations of inositol employed in 

 these experiments are higher than those that occur normally in the blood, 

 no definitive conclusions can be drawn relative to the physiologic role of 

 inositol in cardiac activity. Sonne and Sobotka,^^ in their application of 

 the nephelometric micro bioassay with Saccharomyces carlsbergensis to the 

 determination of inositol, observed levels of from 0.37 to 0.76 mg. per 100 

 ml. in the blood plasma of fasting patients and normal persons. Pooled 

 samples from miscellaneous patients showed values that ranged from 0.54 

 to 1.87 mg. per 100 ml. Moderate increases in the plasma inositol levels 

 followed the ingestion of 1.5 g. of inositol daily. Waldstein and Steigmann"'' 

 gave amounts up to 1 g. of inositol by intravenous injection to patients 

 and concluded that relatively large amounts are well tolerated and appear 

 to be Avithout untoward effects. 



B. GASTROINTESTINAL TRACT 



The effect of inositol on the activity of the stomach and small intestine 

 was studied in dogs by radiographic means by Martin et al.,^^ who found 

 considerable increase in the peristalsis of these organs. No spastic state 

 was produced except a pylorospasm which the authors attributed in part 

 to the constipating diet and in part to a possible contracting effect of the 

 administered inositol on the pyloric sphincter. Other observations are of a 

 more precursory nature but, in general, suggest a stimulating action of 

 inositol on the gastrointestinal tract. For example, Anderson^^ and Bly 

 et al}'^ noted diarrhea in dogs after administration of inositol, whereas 

 Vorhaus et al}^ and Shay^^ administered from 1 to 2 g. of inositol daily to 

 patients without production of gastrointestinal symptoms. As indicated 

 in the discussion on the factors influencing its requirements, inositol prob- 

 es A. Brissemoret and J. Chevalier, Compt. rend. 147, 217 (1908). 



16 A. E. Meyer, Proc. Soc. Exptl. Med. 62, 111 (1946). 



" S. Sonne and H. Sobotka, Arch. Biochem. 14, 93 (1947). 



"» S. S. Waldstein and F. Steigmann, Am. J. Digest. Diseases 19, 323 (1952). 



1* G. J. Martin, M. R. Thompson, and J. de Carvajal-Forero, Am. J . Digest. Diseases 

 8, 290 (1941). 



>9 R. J. Anderson, /. Biol. Chem. 25, 391 (1916). 



2» C. G. Bly, F. W. Heggeness, and E. S. Nasset, /. Nutrition 26, 161 (1943). 



21 M. G. Vorhaus, M. L. Gompertz, and A. P'eder, Am. J. Digest. Diseases 10,45 

 (1943). 



22 H. Shay, Atn. J. Digest. Diseases 10, 48 (1943). 



