| Abstrakt: |
An experimental technic for measuring mean systolic blood pressure and pulse rate of dogs during activity, rest, and natural sleep has been described.1This technic has been applied to normal dogs and to dogs with neurogenic hypertension produced by excision of the 2 carotid sinuses, section of one vagus sympathetic depressor nerve trunk, and division of the remaining depressor nerve.2Variations of blood pressure were noted in both the control and the neurogenic hypertensive dogs. Blood pressures were highest during activity and standing or feeding and lowest during rest and natural sleep. The reduction of pressure of animals with neurogenic hypertension during rest or natural sleep did not reach levels comparable with those reached by normal dogs.The present experiment was undertaken to determine the effect of activity and rest upon dogs with renal hypertension produced by placing capsules about the kidney, Page.3Hypertension was produced in 3 dogs with normal blood pressure by placing silk capsules about both kidneys in 2 (dogs 1 and 2, Fig. 1) and plastic capsules in one (dog 3, Fig. 1). It was produced in a 4th dog by placing a silk capsule about one kidney and removing the other. Blood pressures as determined by direct arterial puncture rose to levels between 190 and 206 mm Hg during the 25 to 36 days that elapsed before the final experiment. Cuffs were then placed about the right iliac and femoral arteries and the animals were prepared for blood pressure determination according to the technic previously described.1After complete recovery from anesthesia blood pressures and pulse rates were recorded at frequent intervals for periods from 49 to 76 hours. The variation and the mean of readings of 3 dogs taken when they were feeding, moving about the cage, standing quietly, lying and resting, or sleeping are illustrated in Fig. 1. |
