Healing of intestinal anastomoses in adrenalectomized rats given corticosterone

To determine the effect of physiological variations in glucocorticoid levels on wound healing, adrenalectomized rats, implanted with corticosterone pellets of varying concentrations, and sham-operated rats were subjected to ileal transection followed by end-to-end anastomosis. Adrenalectomized animals with plasma corticosterone levels less than 2.5 micrograms/dl suffered 25% mortality. In rats surviving 1 wk, bursting pressure of the anastomotic site was measured as an index of wound healing. At plasma corticosterone levels of 3.9-7.4 micrograms/dl, which approximate normal physiological levels, bursting pressure was not significantly different from that in sham-adrenalectomized animals. In adrenalectomized rats with lower or higher corticosterone levels, bursting pressure was significantly reduced. Thus a narrow range of plasma corticosterone is required for optimal wound healing in this model; higher values tend to impair healing, as do subnormal values, perhaps because of slower protein turnover; low values also lead to high mortality.