Regulation of glomerular volume in normal and partially nephrectomized rats
| Autor: | Robert G. Narins, Bruce L. Riser, Pedro Cortes, X Zhao |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Physiology Renal glomerulus Kidney Glomerulus In Vitro Techniques Kidney Nephrectomy Renal Circulation Atrial natriuretic peptide Reference Values Internal medicine Renin–angiotensin system Pressure medicine Animals Humans Rats Wistar Renal circulation Mesangial cell Chemistry Angiotensin II Elasticity Rats Inbred F344 Capillaries Rats Endocrinology medicine.anatomical_structure Renal physiology Compliance |
| Zdroj: | American Journal of Physiology-Renal Physiology. 270:F356-F370 |
| ISSN: | 1522-1466 1931-857X |
| DOI: | 10.1152/ajprenal.1996.270.2.f356 |
| Popis: | Glomerular extracellular matrix accumulation may derive from the stretching of mesangial cells caused by excessive glomerular dilatation. The relationship of glomerular volume (VG) to intraglomerular pressure, expressed as compliance or as mean VG in the isolated, perfused rat glomerulus, was used to analyze factors that regulate VG. Glomeruli were highly distensible over the normal and relevant abnormal range of pressure. Compliance increased directly with basal VG (P < 0.001), i.e., larger glomeruli dilated more than smaller ones at any given pressure. Perfusion with atrial natriuretic peptide did not alter compliance, and inhibitors of nitric oxide synthesis exerted only a trivial effect. VG expansion was consistently reduced by angiotensin II, but this effect was small (3.8%, P < 0.001). After subtotal nephrectomy, compliance increased by 59% in the remnant glomeruli (P < 0.001); 22% of this increase was attributable to structural changes, and the remainder was attributable to the large basal VG of the hypertrophied glomeruli. Thus the major determinants of VG expansion include capillary wall tension, basal VG, and intrinsic distensibility, which is markedly influenced by the character of the extracellular matrix and only slightly altered by an angiotensin II-modified mesangial cell tone. |
| Databáze: | OpenAIRE |
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