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Plasma ACTH and cortisol concentrations were determined at 5-min intervals over a 3- or 4-h sampling period in 2 normal subjects. Time spans studied were 10:00 AM-1:00 PM, 4:00 PM-8:00 PM, 8:00 PM-11:00 PM, and 4:00 AM-8:00 AM. Similar sampling for 3 h, (onset 9:00-9:30 AM) was performed on 4 patients with Cushing's disease, 3 untreated and 1 in remission following pituitary irradiation. Two of these patients were studied on 2 separate occasions. Plasma ACTH was determined by both immunoassay (I) and bioassay (B). Although in general, these studies demonstrated significant correlation between I-ACTH or B-ACTH concentrations and those of plasma cortisol, a striking finding in both subject categories was the presence of 30- to 50-min episodes during which marked rises in both I- and B-ACTH concentrations occurred without concomittant, or markedly diminished, increments in plasma cortisol concentrations. This could not be explained by biological inactivity of the ACTH, since a highly significant correlation was present between I- and B-ACTH concentrations at all times; r values ranged between 0.86 and 0.98 for normal subjects, and 0.76 and 0.96 for patients with Cushing's disease. The lack of correlation in these episodes also does not appear to be secondary to an 11-beta-hydroxylase block, differences in the rate of change of plasma ACTH concentrations, lack of adrenal "priming" by prior ACTH or incapacity of the adrenal gland to further increase secretion. I/B ACTH ratios were similar in the normal subjects (1.42-1.64) and in the patients with Cushing's disease (1.27-1.47). "Apparent" ACTH half lives calculated from "peaks" of ACTH secretion were 7-12 min for I-ACTH and 3-9 min for B-ACTH in the normal subjects; and 9-13 min and 7-9 min respectively, in the patients with Cushing's disease. Mean plasma ACTH I-and B-concentrations at comparable time periods were higher in patients with active Cushing's disease than in normal subjects. These studies also indicate that in Cushing's disease, the abnormality present resides in ACTH regulatory mechanisms, not in the nature of the ACTH secreted. Approximation of the total amount of immunoassayable ACTH secreted in one normal subject over a 24-h period yielded a value of 73 mug. Total mug/h secreted in the 2 normal subjects were highest in the hour preceding awakening (6:30-7:30 AM; 12.9 and 12.2 mug/h); were 5.3 and 4.0 mug/h between 10:00-11:00 AM, and 1.4 and 1.7 mug/h between 9:00-10:00 PM. In the 3 patients with clinically active Cushing's disease, apparent ACTH secretion between 10:00-11:00 AM varied from 19.2-34.3 mug/h, the magnitude of such secretion being positively correlated with the extent of increased adrenal cortical activity present.

If you would like to write for this, or any other Emerald publication, then please use our Emerald for Authors service information about how to choose which publication to write for and submission guidelines are available for all. Please visit www.emeraldinsight.com/authors for more information. About Emerald www.emeraldinsight.comEmerald is a global publisher linking research and practice to the benefit of society. The company manages a portfolio of more than 290 journals and over 2,350 books and book series volumes, as well as providing an extensive range of online products and additional customer resources and services.Emerald is both COUNTER 4 and TRANSFER compliant. The organization is a partner of the Committee on Publication Ethics (COPE) and also works with Portico and the LOCKSS initiative for digital archive preservation. AbstractPurpose -Recent misconduct and highly questionable behavior has fostered considerable distrust, cynicism, and antagonism among the populace toward the leadership of virtually all social institutions. This paper aims to examine the impact of ethics training on business students values. Design/methodology/approach -Focuses on the central question whether exposure to ethical dilemmas and discussions in the classroom setting will lead to new paradigms of leadership incorporating instrumental values. Findings -The results support the contention that senior level students were influenced in their perceptions of the importance of instrumental values in comparison to freshmen. As hypothesized no difference was found between men and women in both the importance and reinforcement of the instrumental values examined. The results do not support the contention that increased emphasis on ethics in textbooks and courses has had a significant impact. Practical implications -Directions for future training are considered in light of the findings. Originality/value -Points to the conclusion that current models of business education are not helping to reinforce instrumental values.