In a canine experimental model, femora were lengthened 2.5 to 3.0
centimeters over a one-minute period. Systolic blood-pressure elevation
averaged forty millimeters of mercury and diastolic blood-pressure
elevation, twenty-two millimeters of mercury. The average peak arterial
pressure was 193/115 millimeters of mercury. The effects of sympatholytic
agents on the experimental model were tested. Alpha-adrenergic blockade by
phenoxybenzamine, total-body catecholamine depletion by reserpine, and
sympathetic ganglionic blockade by trimethaphan camphorsulfonate all
inhibited the rise in arterial pressure, but beta-adrenergic blockade by
propranolol did not. A differential spinal anesthetic with Xylocaine
solution dramatically decreased the elevation in arterial pressure.