摘要：

The plasma corticosterone (PC) levels of mice adapted to 27–28 °C rose significantly when they were exposed to the cold at −10 °C until they became comatose, the increase being significantly less during a second similar exposure a week later. The PC elevations which occurred at −10 °C before the mice became comatose could be due in some degree to renal impairment, as indicated by increases in blood urea nitrogen and plasma creatinine levels during the first and second exposures, respectively. However, hemoconcentration as indicated by changes in the hemoglobin level could not account for the increase in the PC level. Mice that became comatose at −10 °C also had significantly elevated PC levels which were probably not primarily due to hemoconcentration or renal impairment. Mice recovering from coma in the warmth also had elevated PC levels for 6 h after the first exposure and for 1 day after the second one. At 1 and 7 days following exposure to the cold, the adrenal cortex no longer appeared to be hyperfunctional. Renal function appeared to have been impaired for 4 h following the first exposure and for at least 7 days after the second one. This impairment could account for the elevated PC levels and lower urinary corticosteroid amounts observed on the first day following the second exposure.

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