Lymphocyte and polymorphonuclear enzymes in stress: II. Effect of the stress of restraint on rabbit leukocyte protein, aldolase, and lactate dehydrogenases

Abstract

Rabbits were stressed by restraint in the supine position. The buoyantdensity characteristics, protein, aldolase, LDH and LDH isozyme contents of their differentially separated leukocytes after this stress were compared with leukocytes of normal rabbits bled only once and with leukocytes of unstressed rabbits bled according to the schedule set for the stressed rabbits. The separation into cell types was reproducible. An increase in PMN after restraint was reflected in an increase in the cells of the heaviest density layer (sp gr 1.090). Lymphocytes from the top layer showed increments in protein and LDH, but no change in aldolase, immediately after a 4- to 6-hour period of restraint. These changes were not demonstrated by lymphocytes from the lower layer. The stress of restraint caused a greater increase in LDH of PMN from the bottom gradient than it did in PMN from the gradient above it. These changes were not paralleled by total protein changes. Protein, aldolase, and LDH were increased in the mixed population of cells obtained from gradient layer 3 sp gr 1.068) immediately after restraint. Some enzyme and protein changes in leukocytes were demonstrable 24 hours after the applied stress. Differences in the quantitative distribution of LDH isozymes in repeatedly bled and restrained rabbits were noted.