PHYSIOLOGY OF SMOOTH AND STRIATED MUSCLE 



565 



Experiment 58 

 April 28, 1911 

 Portions of stomach muscle^ of bull- 

 frogs Nos. 34, 35, 36, 37, 38, 39, 40, 41, 

 42 and 43, weighed fresh 6.3422 grams 

 This portion of muscle was analyzed 

 for potassium and sodium and found to 

 contain 0.3437 per cent potassium and 

 0.0804 per cent sodium 



1 Each piece of stomach muscle was 

 cut into a cardiac and pyloric half, 

 and the portions of muscle used in this 

 experiment and in Experiment 59 con- 

 tained equal numbers of cardiac and 

 pyloric halves 



Experiment 59 

 A-pril 28, 1911 



Portions of stomach muscle- of bull- 

 frogs Nos. 34, 35, 36, 37, 38, 39, 40, 41, 

 42 and 43, weighed fresh 6.3048 grams 



This portion of muscle was placed for 

 five hours in 7.5 per cent cane sugar so- 

 lution, which was frequently stirred and 

 changed three times. In all about 200 

 cc. of the sugar solution were used. At 

 the end of the five hours the muscle 

 weighed 6.3091 grams, and was still 

 highly irritable. It was then analyzed 

 for potassium and sodium and found to 

 contain 0.3299 per cent potassium and 

 0.0460 per cent sodium. 



The fresh muscle contained 0.3437 

 per cent potassium and 0.0804 per cent 

 sodium. Therefore, 0.3437-0.3299 or 

 0.0138 per cent potassium, and 0.0804- 

 0.0460 or 0.0344 per cent sodium may be 

 supposed to have diffused out into the 

 sugar solution. 



Temperature varied between 22° and 

 25° 



2 See footnote to Experiment 58. 



Experiment 60 

 May 22, 1911 

 Portion of stomach muscle of bull- 

 frog 44, weighed fresh 0.273 gram. 

 10.45 A.M. immersed in 7.5 per cent 



cane sugar solution 

 11.00 A.M. weighed 0.310 gram, fibers 



somewhat lengthened 

 11.45 A.M. weighed 0.327 gram, fibers 

 considerably lengthened 

 1.45 p.m. weighed 0.334 gram, fibers 

 still considerably length- 

 ened, transferred to fresh 

 sugar solution 

 3.45 P.M. weighed 0.391 gram, fibers 

 considerably longer than 

 at 1.45 and still fairly irri- 

 table 

 Temperature varied between 26° and 

 29° 



Experiment 61 

 Mmj 22, 1911 



Portion of stomach muscle of bull- 

 frog 44, weighed fresh 0.208 gram 

 10.49 A.M. immersed in mixture made 

 up of 1 part Ringer and 

 19 parts 7.5 per cent cane 

 sugar solution 

 11.04 a.m. weighed 0.214 gram, fibers 

 have not changed in length 

 11.49 a.m. weighed 0.210 gram, fibers 

 now somewhat shortened 

 1.49 p.m. weighed 0.205 gram, fibers 



still shortened 

 3.49 p.m. weighed 0.214 gram, fibers 

 still shortened, and fairly 

 irritable 

 Temperature varied between 26° and 

 29° 



