70 



EXEECISE XI 



SPECIFIC GEAVITY OF BLOOD; PERFUSION OF EENAL VESSELS WITH 

 EINGER-LOCKE ; INFLUENCE OF ADRENAL EXTRACT AND AMYL 

 NITRITE; HAEMOLYSIS. 



I. See that the decapitate preparation provided is being ventilated 

 properly and in good condition. 



II. Fill six of the small test-tubes in the rack about five-sixths full 

 with sp. gr. fluids of the following gravities : 1-054, 1-050, 1-045, 1-042, 

 1-038, 1034, 1-030. The test-tubes should be arranged in definite order in 

 the rack and the number of the sp. gr. of the fluid in each tube written 

 opposite on the rack. Capillary pipettes rectangularly bent at tip are 

 provided. Arm two of the capillary pipettes with rubber tubing, and place ten 

 more of the pipettes in readiness for speedy use. 



See that the pressure apparatus for perfusion of the kidney is in order. 

 Arrange the height of the reservoir so that it will stand about 70 cm. 

 above the preparation on the experiment table. 



Obs.''47. III. 1, Operation. Place the decapitate preparation supine, with the 



Sp. gr. o t e iijn]3g symmetrically extended by clip-weights attached to the feet. 



A. To the skin above the left knee attach a heavy clip-weight, 

 keeping that thigh somewhat abducted. Clip the hair from the left groin. 

 Make an incision about 4 cm. long through the skin over the fold 

 of groin about 1 cm. lateral to the mid-line of the groin. Reflect the 

 skin and subcutaneous fat towards the medial side of the thigh, exposing 

 the femoral nerve and the femoral vessels (PL IX, fig. 6) as they enter 

 the thigh from under Poupart's ligament. Sever the femoral nerve at 

 its exit from the psoas muscle. Close below Poupart's ligament it will 

 be seen that the femoral artery and vein each have a branch passing later- 

 ally outwards under the femoral nerve ; this branch is the circumfiexa 

 lateralis (PL IX, fig. 6). About 12 mm. lower down another branch leaves 

 the femoral artery on its medial side. With the curved mounted needle 

 pass a fine thread under the femoral artery about 5 mm. proximal to 

 circumfiexa branch, also similar threads under the artery at two other 

 points, one about 5 mm. distal to the first ligature, and another close above 

 the junction of femoral with medial branch. Tie loosely the first loop of a 

 reef-knot with the middle ligature, and make loops with the two others. 

 Attach an artery-forceps to the most distal loop. 



