Engeland W C, Byrnes G J, Gann D S
Endocrinology. 1982 Jun;110(6):1856-60. doi: 10.1210/endo-110-6-1856.
The response of plasma ACTH and the secretory response of cortisol to moderate hemorrhage were determined in awake dogs in the morning (AM) and evening (PM). Whereas the magnitudes of the response of ACTH were similar in the AM and PM, the magnitude of the secretory response of cortisol was significantly greater in the AM compared to that in the PM. At both times of day, heart rate, mean arterial pressure, and secretory rates of epinephrine after hemorrhage were similar. These findings suggest that AM-PM differences in stimuli produced by moderate hemorrhage cannot explain the differences in the secretion of cortisol. Instead, AM-PM changes in adrenocortical sensitivity to endogenous ACTH after hemorrhage determine the AM-PM differences in the secretion of cortisol.
在清晨（AM）和傍晚（PM）对清醒犬进行中度出血，测定血浆促肾上腺皮质激素（ACTH）的反应以及皮质醇的分泌反应。虽然ACTH反应的幅度在上午和下午相似，但与下午相比，上午皮质醇的分泌反应幅度明显更大。在一天中的这两个时间，出血后的心率、平均动脉压和肾上腺素分泌率均相似。这些发现表明，中度出血产生的刺激在上午和下午的差异并不能解释皮质醇分泌的差异。相反，出血后肾上腺皮质对内源性ACTH敏感性的上午-下午变化决定了皮质醇分泌的上午-下午差异。
