76 LABORATORY MANUAL OF GENERAL PHYSIOLOGY 



Marshall, Physiol. Rev., 14: 133, 1934. Cf. also Evans' "Recent Advances 

 in Physiology," 5th Ed., p. 377, 1936. Text pp. 246, 249, 263. 



16. Perfusion of the Liver. — Secure a capillary cannula with a lip (must 

 be made by a glass blower). If special cannulae are not available use 

 cannulae described in Ex. 15a. Cut one side of the body wall of a frog. 

 Lay back the body wall without injury to the vena abdominalis. Tie 

 the cannula in an incision in the gall bladder. To exclude circulation from 

 the hepatic portal vein a ligature must be tied tightly around the oesopha- 

 gus and fold of intestine containing the pancreas. Perfuse the abdominal 

 vein with 0.0005% eriocyanin (this dye can be obtained from K. Hollborn, 

 Leipzig, through Pfaltz and Bauer, New York). The dye will emerge 

 from the cannula in a 0.5% concentration within two hours (or the gall 

 bladder will become blue) cf. Hober and Titajew, Arch. ges. Physiol., 

 223:180,1929. Text p. 249. 



Directions for experiments 15 and 16 were prepared by R. W. Lippman. 



XII. TEMPERATURE CHARACTERISTICS 



(See Appendix of Text for Index to Temperature Characteristics) 



In these experiments graphs must be plotted and the best straight line 

 drawn through the points. Calculate n from this line. Text p. 387. 



1. CO2 Production of Muscle. — Three test tubes are supported in holes 

 drilled in a board resting on top of a thermostat jar. Add five drops of 

 Phenol-red to standards and to the observation tube containing frog's 

 muscle in 10 cc. Ringer. Determine time for pH to change from 7.6 to 

 7.4 at several temperatures from 15 to 25°. The standard buffer solutions 

 can be made up to any fixed pH values in this range. Constant tempera- 

 atures must be maintained. Calculate the apparent temperature 

 characteristic. 



Begin experiment as soon as possible for the changes are slow. The 

 central tube containing the muscle and Ringer's solution will be more 

 alkaline than both standards but will change as CO2 is given off. Replace 

 Ringer for each temperature. The same muscle must be used. Large 

 muscles produce most rapid changes (entire leg may be used). Keep 

 tubes corked. Match tubes at same level cf. Crozier, J. Gen. Physiol., 

 7: 189, 1924. 



2. Breathing Movements of Frog. — Determine the time for ten pharyn- 

 geal movements in a frog (large females are sedentary) at as many tem- 

 peratures as possible between 7 and 28°C. Immerse the animal in an air 

 tight preserve jar weighted with buck shot covered with paraffin. Cover 

 thermostat with paper leaving peep-hole for observation. Allow 10 mins. 

 for temperature adjustment. Avoid all possible disturbance. Remove 

 the lid of jar at each change for renewal of air. Calculate the temperature 

 characteristic with the Arrhenius equation. 



