Deleterious effects of calcium channel blockade on pressure transmission and glomerular injury in rat remnant kidneys.

Hypertensive mechanisms are postulated to play a major role in the progressive glomerulosclerosis (GS) after renal mass reduction. But, in contrast to converting enzyme inhibitors, BP reduction by calcium channel blockers, has not provided consistent protection. Radiotelemetric BP monitoring for 7 wk was used to compare nifedipine (N) and enalapril (E) in the rat approximately 5/6 renal ablation model. After the first week, rats received N, E, or no treatment (C). The overall averaged systolic BP in C (173 +/- 7 mmHg) was reduced by both E and N (P < 0.001), but E was more effective (113 +/- 2 vs. 134 +/- 3 mmHg, P < 0.01). GS was prevented by E (2 +/- 1 vs. 26 +/- 5% in C) but not by N (25 +/- 6%). GS correlated well with the overall averaged BP in individual animals of all groups, but the slope of the relationship was significantly steeper in N compared with C+E rats (P < 0.02), suggesting greater pressure transmission to the glomeruli and GS for any given BP. Since autoregulatory mechanisms provide the primary protection against pressure transmission, renal autoregulation was examined at 3 wk in additional rats. Autoregulation was impaired in C rats, was not additionally altered by E, but was completely abolished by N. These data demonstrate the importance of autoregulatory mechanisms in the pathogenesis of hypertensive injury and suggest that calcium channel blockers which adversely affect pressure transmission may not provide protection despite significant BP reduction.

[1]  A. V. Wolf Demonstration concerning pressure-tension relations in various organs. , 1952, Science.

[2]  H. D. de Wardener,et al.  Effect of Increased Renal Venous Pressure on Circulatory “Autoregulation” of Isolated Dog Kidneys , 1959, Circulation research.

[3]  T. Shimamura,et al.  A progressive glomerulosclerosis occurring in partial five-sixths nephrectomized rats. , 1975, The American journal of pathology.

[4]  S. Klahr,et al.  Pathogenesis of the glomerulopathy associated with renal infarction in rats. , 1976, Kidney international.

[5]  E. Weibel Practical methods for biological morphometry , 1979 .

[6]  J. Fleiss,et al.  Some Statistical Methods Useful in Circulation Research , 1980, Circulation research.

[7]  R. Cohen,et al.  Power spectrum analysis of heart rate fluctuation: a quantitative probe of beat-to-beat cardiovascular control. , 1981, Science.

[8]  B. Brenner,et al.  Hyperfiltration in remnant nephrons: a potentially adverse response to renal ablation. , 1981, The American journal of physiology.

[9]  C. Mogensen Long-term antihypertensive treatment inhibiting progression of diabetic nephropathy , 1982, British medical journal.

[10]  B. Brenner,et al.  Predominance of hemodynamic rather than metabolic factors in the pathogenesis of diabetic glomerulopathy. , 1985, Proceedings of the National Academy of Sciences of the United States of America.

[11]  M. Epstein,et al.  Effects of calcium antagonists on renal hemodynamics. , 1985, The American journal of physiology.

[12]  B. Brenner Nephron adaptation to renal injury or ablation. , 1985, The American journal of physiology.

[13]  L. Navar,et al.  Effects of Calcium Channel Blockade on Renal Vascular Resistance Responses to Changes in Perfusion Pressure and Angiotensin‐Converting Enzyme Inhibition in Dogs , 1986, Circulation research.

[14]  M. Turiel,et al.  Power Spectral Analysis of Heart Rate and Arterial Pressure Variabilities as a Marker of Sympatho‐Vagal Interaction in Man and Conscious Dog , 1986, Circulation research.

[15]  B. Brenner,et al.  Therapeutic advantage of converting enzyme inhibitors in arresting progressive renal disease associated with systemic hypertension in the rat. , 1986, The Journal of clinical investigation.

[16]  E. Lewis,et al.  Renal autoregulation and vulnerability to hypertensive injury in remnant kidney. , 1987, The American journal of physiology.

[17]  D. Harris,et al.  Verapamil protects against progression of experimental chronic renal failure. , 1987, Kidney international.

[18]  J. Neugarten,et al.  Hypertension and renal diseases. , 1987, American journal of kidney diseases : the official journal of the National Kidney Foundation.

[19]  D. Harris,et al.  Glomerular hemodynamic adaptations in remnant nephrons: effects of verapamil. , 1988, The American journal of physiology.

[20]  J. Olson,et al.  Nonimmunologic mechanisms of glomerular injury. , 1988, Laboratory investigation; a journal of technical methods and pathology.

[21]  C. Johnston,et al.  The contribution of systemic hypertension to progression of chronic renal failure in the rat remnant kidney: effect of treatment with an angiotensin converting enzyme inhibitor or a calcium inhibitor. , 1988, Journal of hypertension.

[22]  W. Deen,et al.  "Intact nephrons" as the primary origin of proteinuria in chronic renal disease. Study in the rat model of subtotal nephrectomy. , 1988, The Journal of clinical investigation.

[23]  S. Klahr,et al.  Progression of renal disease. , 1988, Seminars in nephrology.

[24]  M. Mihatsch,et al.  Long-term enalapril and verapamil in rats with reduced renal mass. , 1989, Kidney international.

[25]  A. Fogo,et al.  Glomerular hemodynamic changes vs. hypertrophy in experimental glomerular sclerosis. , 1989, Kidney international.

[26]  A. Fogo,et al.  Effects of antihypertensive drugs on glomerular morphology. , 1989, Kidney international.

[27]  L. Navar,et al.  Disparate effects of Ca channel blockade on afferent and efferent arteriolar responses to ANG II. , 1989, The American journal of physiology.

[28]  L. Raij,et al.  Angiotensin converting enzyme inhibitors and progression of chronic renal failure. , 1990, Kidney international. Supplement.

[29]  T. Hostetter,et al.  Adverse effects of growth in the glomerular microcirculation. , 1990, The American journal of physiology.

[30]  E. Lewis,et al.  Absence of glomerular injury or nephron loss in a normotensive rat remnant kidney model. , 1990, Kidney international.

[31]  W. Arendshorst,et al.  Tubuloglomerular feedback and autoregulation in spontaneously hypertensive rats. , 1990, The American journal of physiology.

[32]  D J Marsh,et al.  Tubuloglomerular feedback dynamics and renal blood flow autoregulation in rats. , 1991, The American journal of physiology.

[33]  G. Bakris Renal effects of calcium antagonists in diabetes mellitus. An overview of studies in animal models and in humans. , 1991, American Journal of Hypertension.

[34]  S. Anderson Renal Hemodynamic Effects of Calcium Antagonists in Rats With Reduced Renal Mass , 1991, Hypertension.

[35]  T. Meyer,et al.  Glomerular hypertrophy accelerates hypertensive glomerular injury in rats. , 1991, The American journal of physiology.

[36]  J. Westcott,et al.  Impaired autoregulation of glomerular capillary hydrostatic pressure in the rat remnant nephron. , 1991, The Journal of clinical investigation.

[37]  M. Picken,et al.  Prostaglandins do not mediate impaired autoregulation or increased renin secretion in remnant rat kidneys. , 1992, The American journal of physiology.

[38]  M. Di Rienzo,et al.  Twenty-four hour blood pressure variability: clinical implications. , 1992, Kidney international. Supplement.

[39]  B. Brenner,et al.  Nifedipine versus fosinopril in uninephrectomized diabetic rats. , 1992, Kidney international.

[40]  A. Fogo,et al.  Blood pressure-independent effect of angiotensin inhibition on vascular lesions of chronic renal failure. , 1992, Kidney international.

[41]  M. Epstein Calcium antagonists and the kidney: future therapeutic perspectives. , 1993, American journal of kidney diseases : the official journal of the National Kidney Foundation.

[42]  K A Griffin,et al.  Role of endothelium-derived nitric oxide in hemodynamic adaptations after graded renal mass reduction. , 1993, The American journal of physiology.

[43]  L. Dworkin,et al.  Calcium antagonists and converting enzyme inhibitors reduce renal injury by different mechanisms. , 1993, Kidney international.

[44]  M. Picken,et al.  Continuous telemetric blood pressure monitoring and glomerular injury in the rat remnant kidney model. , 1993, The American journal of physiology.

[45]  Hermann Hailer Calcium antagonists and cellular mechanisms of glomerulosclerosis and atherosclerosis. , 1993 .

[46]  K. Griffin,et al.  Renal ablation acutely transforms 'benign' hypertension to 'malignant' nephrosclerosis in hypertensive rats. , 1994, Hypertension.

[47]  M. Picken,et al.  Method of renal mass reduction is a critical modulator of subsequent hypertension and glomerular injury. , 1994, Journal of the American Society of Nephrology : JASN.

[48]  M. Picken,et al.  Radiotelemetric BP monitoring, antihypertensives and glomeruloprotection in remnant kidney model. , 1994, Kidney international.

[49]  J. Bartges,et al.  Hypertension and renal disease. , 1996, The Veterinary clinics of North America. Small animal practice.