Referring to the mosaic theory of Page, the authors present an overview of recent topics related to the participation of endocrine and auto-paracrine factors, such as steroids, ouabain-like substance, insulin, renin-angiotensin and endothelin, in the pathogenesis of primary hypertension. These factors promote the development of hypertension in either a direct or indirect manner; in addition, they promote, to some extent, the proliferation of vascular smooth muscle cells. Future research should attempt to elucidate interactions between these factors in cardiovascular tissues and to define how these factors interact with various vasodepressor substances to regulate blood pressure. (Hypertens Res 1995; 18: 171-179) Key Words: steroids, ouabain-like substance, insulin, renin-angiotensin, endothelin, primary hypertension Although primary hypertension accounts for 95% of all cases of hypertension, the multifaceted mosaic concept for the pathogenesis of this disease, proposed by Page (1) in 1963, still remains valid. One can only say that a number of new facets, which integrate closely into the mosaic theory, have appeared during the past few decades.The blood pressure can be defined as the product of cardiac output (pumping action of the heart) and peripheral resistance (arterial tone) . Moreover, complex mechanisms, involving interactions among genetic, hormonal and physical factors, affect each of the determinants. Recently, the potential roles of various hormones in modulating arterial tone, not only by the functional regulation of resistance vessels but also by their structural alterations (remodeling), have attracted considerable interest. The reason for revived interest in the hormonal aspects of the pathogenesis of primary hypertension seem to be due, in part, to the discovery of new vasoactive substances derived from the vascular tissue, acting as an auto-paracrine organ. Assuming a certain subgroup of primary hypertension can be identified as being caused by a state of vasopresssor hormone excess or dilator deficiency, that subgroup then should be categorized as a form of secondary (endocrine) hypertension.In the present review, the authors present an overview of recent advances in endocrinological aspects of primary hypertension and address questions that have emerged as a result of advances in the research of altered steroid metabolism, ouabainlike substances, the renin-angiotensin-aldosterone system, and endothelin.
Altered Steroid MetabolismDuring the 1960s and 1970s, Kornel et al. (2-4) reported a series of articles suggesting that altered cortisol metabolism results in increased excretion of polar derivatives of cortisol (non-A-ring-reduced 20-hydroxysteroids and 6R-hydroxysteroids). They also provided some evidence for the predominant role of sulfoconjugation rather than glucuronoconjugation in primary hypertension. However, the precise implications of these findings in the pathogenesis of primary hypertension are still unclear.Recently, the pathophysiological importance of cortisol inactivation by...
