This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: How Do Glucocorticoids Influence Stress Responses? Integrating Permissive, Suppressive, Stimulatory, and Preparative Actions* ROBERT M. SAPOLSKY, L. MICHAEL ROMERO, AND ALLAN U. MUNCK* Department of Biological Sciences (R.M.S.), Stanford University, Stanford, California 94305; Department of Biology (L.M.R.), Tufts University, Medford, Massachusetts 02155; and Department of Physiology (A.U.M.), Dartmouth Medical School, Lebanon, New Hampshire 03756 ABSTRACT The secretion of glucocorticoids (GCs) is a classic endocrine re- sponse to stress. Despite that, it remains controversial as to what purpose GCs serve at such times. One view, stretching back to the time of Hans Selye, posits that GCs help mediate the ongoing or pending stress response, either via basal levels of GCs permitting other facets of the stress response to emerge efficaciously, and/or by stress levels of GCs actively stimulating the stress response. In con- trast, a revisionist viewpoint posits that GCs suppress the stress response, preventing it from being pathologically overactivated. In this review, we consider recent findings regarding GC action and, based on them, generate criteria for determining whether a particular GC action permits, stimulates, or suppresses an ongoing stress- response or, as an additional category, is preparative for a subsequent stressor. We apply these GC actions to the realms of cardiovascular function, fluid volume and hemorrhage, immunity and inflammation, metabolism, neurobiology, and reproductive physiology. We find that GC actions fall into markedly different categories, depending on the physiological endpoint in question, with evidence for mediating ef- fects in some cases, and suppressive or preparative in others. We then attempt to assimilate these heterogeneous GC actions into a physi- ological whole. ( Endocrine Reviews 21: 5589, 2000) I. The Decline and Modern Revision of Glucocorticoid Physiology II. Definition of Terms, and Criteria for Analyzing the Role of GCs in the Stress Response A. The prototypical stress response B. Definitions of the classes of GC actions C. Criteria for analyzing the role of GCs in the stress response III. GC Actions in the Context of These Criteria A. Cardiovascular effects B. Fluid volume and hemorrhage C. Immunity and inflammation D. Metabolism E. Neurobiological effects F. Reproductive physiology IV. An Integration A. The logic of the heterogeneity of categories of glu- cocorticoid actions B. An appreciation of permissive glucocorticoid actions C. The relevance of preparative actions in an ethologi- cal context V. Molecular Mechanisms Underlying Actions of GCs in Stress A. Permissive and suppressive actions: MRs or GRs?...
View Full Document
This note was uploaded on 07/17/2008 for the course PSYCH 501 taught by Professor Bruno during the Winter '08 term at Ohio State.
- Winter '08
- The Hours