MUSCLE-NERVE. 



KCC appears before ACC. In well-marked degeneration ACC 

 appears first. 



Experiment. Narcotize a rabbit with morphine and ether. Ex- 

 pose and cut one sciatic nerve as high up as possible. Sew up the 

 wound and test the muscle at intervals of two days for the reaction 

 of degeneration. 



XXIV. ACTION OF CERTAIN DRUGS UPON THE SINGLE 

 MUSCLE TWITCH. 



1. Veratrine. Make a saturated solution of veratrine in 0.6- 

 per-cent sodium-chloride solution. Pith a frog and inject, under 

 the skin, about five drops of the veratrine solution. In a few min- 

 utes (ten to fifteen), if the frog be made to jump, it will be seen 

 that the recovery of the flexed position of the hind limbs is very 

 slowly brought about. A little later, a spasm of both limbs 

 occurs at every attempt to jump. The flexor muscles, being the 

 weaker, are overpowered by the extensors. 



Make a gastrocnemius-sciatic preparation from the frog. At- 

 tach the tendon to the writing-lever of a myograph. Adjust the 

 point of the lever to the smoked paper of a drum revolving at me- 

 dium speed. Stimulate the nerve with a single maximal break 

 shock from an inductorium. How does the recorded contraction 

 compare with the normal muscle twitch ? 



2. Adrenalin (active principle of the suprarenal gland). In- 

 ject into the dorsal lymph sac of a pithed frog 10 drops of a i to 

 10,000 solution of adrenalin chloride. After ten minutes, make 

 a muscle preparation and proceed as in i . Is there any departure 

 from the normal muscle twitch ? Prepare the muscle and nerve of 

 the other leg or of another frog. Immerse the muscle in the 

 adrenalin for a few minutes and again record a contraction. 



XXV. INVOLUNTARY MUSCLE. 



Synonymes : Plain or smooth, slow, non-striated, i . Remove the 

 stomach from a pithed frog. Make two parallel cuts through the 

 viscus running at right angles to the long axis and about one-half 



[45] 



