The influence of immobilization stress on natural killer cytotoxic activity in halothane susceptible and resistant pigs.
In halothane-susceptible (Hal+) and halothane-resistant (Hal-) Belgian Landrace pigs, the influence of immobilization stress on cytotoxic activity of natural killer (NK) cells was evaluated. Four hour immobilization causes biphasic changes in cytotoxicity, i.e. an initial increase followed by a subsequent depression. In both groups of pigs stress-induced suppression of NK cell activity lasted for several days in the post stress period. Throughout the experiment, i.e. before, during and after stress, the level of cytotoxicity was higher in Hal+ than in Hal- pigs.