118 CAFFEINE, 



CAFFEINE. 



1. Carefully make 2 muscle preparations, place them in glass capsules, connect 

 with weighted muscle levers, and obtain contraction records using minimum break 

 shocks only. Fill one capsule with Locke's solution, and the other capsule with Locke's 

 solution containing 0.1% Caffeine. Obtain comparative contraction records every 

 half minute. 



2. To a cat administer 0.120 Gm. Caffeine. Take observations of pulse, respira- 

 tion, and nervous state. 



3. Etherize a large female cat or rabbit. Connect up recording apparatus, and 

 obtain normals of respiration and circulation. Into the bladder introduce a suitable 

 catheter ; distend bladder gently with normal saline ; then arrange for collecting urine 

 in centesimal metric graduate. At the rate of % m il every 15 seconds, run into the 

 jugular vein Caffeine 2% in Locke's solution (kept at 38 C.). Take continuous 

 record, and note amount of urine passed every 20 minutes. Note any symptoms that 

 may develop. 



Check this experiment by repeating it on another cat of equal weight and condi- 

 tion, but omitting the Caffeine. 



4. With a subject in a comfortable position, obtain his normal pulse, respiration, 

 blood-pressure, and temperature. With aesthesiometer test his forearm for tactile dis- 

 crimination. Test his reaction time for sight, hearing, and feeling. Make speed tests 

 of his mental activity, using the antonym test, the imagery and multiplication tests. 

 Administer 2 mils of a 10% solution Caffeine Citrate subcutaneously into loose cellular 

 tissue. Make usual graphs. Take intellection tests every 45 minutes. Measure urine 

 excreted every hour for 8 hours. 



5. Make comparative observations on three similar subjects, to one of whom is 

 administered 0.3 Gm. Caffeine, to the second is given a cup of hot coffee, to the third 

 is given a cup of cold coffee of the same brew. Note the several systems, including 

 the excretory. 



6. In the hospital assignment, especially study the effect on the heart of Caffeine, 

 wherever administered. 



7. From all your observations, and from your readings, write a summary of the 

 leading effects produced by Caffeine. 



