Impaired effect of nitric oxide synthesis inhibition on tubuloglomerular feedback in hypertensive rats
| Autor: | C. Thorup, A. E. G. Persson |
|---|---|
| Rok vydání: | 1996 |
| Předmět: |
Male
medicine.medical_specialty Physiology Kidney Glomerulus Nitric Oxide Nitroarginine Rats Inbred WKY Feedback Nitric oxide Kidney Tubules Proximal chemistry.chemical_compound Rats Inbred SHR Internal medicine Pressure medicine Animals Tubuloglomerular feedback Nitric oxide synthesis biology Rats Inbred Strains Capillaries Rats Nitric oxide synthase Kidney Tubules Endocrinology chemistry Hypertension biology.protein Nitric Oxide Synthase Glomerular Filtration Rate |
| Zdroj: | American Journal of Physiology-Renal Physiology. 271:F246-F252 |
| ISSN: | 1522-1466 1931-857X |
| DOI: | 10.1152/ajprenal.1996.271.2.f246 |
| Popis: | Experiments were conducted to compare the effects of intratubular inhibition [N omega-nitro-L-arginine (L-NNA)] of nitric oxide (NO) on the tubuloglomerular feedback (TGF) mechanism between anesthetized spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) and between the Milan hypertensive (MHS) and the Milan normotensive (MNS) strains of rats. Changes in proximal tubular stop-flow pressure (Psf) in response to various loop of Henle perfusion rates and measurements of early proximal flow rate (EPFR) were used to characterize TGF. Maximal drop in Psf (delta Psf) were used to indicate TGF reactivity and the flow rate eliciting half-maximal delta Psf (turning point; TP) to indicate TGF sensitivity. Under control conditions, TGF sensitivity was significantly higher in SHR than in WKY, but, after L-NNA infusion, TP was decreased in WKY and not in SHR. L-NNA infusion increased delta Psf by 95% in WKY but to a lesser extent (by 26%) in SHR. In the same way, L-NNA decreased TP in MNS but not in MHS. The increase in delta Psf was 99% in MNS but only 32% in MHS. The EPFR reduction after TGF activation was significantly increased in WKY and MNS but relatively unchanged in SHR and MHS. The results show that the effect of intratubular NO synthase inhibition on TGF is impaired in both strains of hypertensive rats. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|