Endocrine Abstracts

Ultradian rhythms of glucocorticoid hormones is crucial for optimal glucocorticoid-target gene expression, and therefore it is important to understand the mechanisms regulating glucocorticoid pulsatility and how it becomes disrupted in disease. I will discuss our recent findings on how the adrenal steroidogenic pathway responds dynamically to pulses of ACTH, both in vitro in adrenocortical cells and in vivo in the rat, and how these dynamics become disrupted in response to inflammatory stress resulting in abnormal circulating glucocorticoids levels. I will also show some recent data on the long-term effect of chronic synthetic glucocorticoid treatment on HPA axis dynamics and on adrenal functions.