Nitric oxide and preglomerular vascular lesions in lyon spontaneously hypertensive rats.

Abstract

Accumulation of Sudan black-stainable (SB+) lipids is a hallmark of the focal inflammato-proliferative lesions that develop along preglomerular vessels in N G-nitro-L-arginine methyl ester (L-NAME) and angiotensin II hypertensive rats. We extended our findings to genetically hypertensive Lyon (LH) rats aged 14 and 30 weeks and to age-matched normotensive (LN) rats. Vessels were isolated by HCl maceration. Despite high systolic blood pressure (SBP), hypercholesterolaemia, albuminuria and increased interlobular and afferent arteriolar media thickness, SB+ lesions were rarely found in LH rats, regardless of age. To probe nitric oxide as a potential source of vascular protection, 14-week-old LN and LH rats received L-NAME for 10 days (20 mg kg-1 day-1, per os), which increased SBP to 174 +/- 5 and to >200 mmHg, respectively. It induced formation of focal SB+ lesions less frequently in LN than LH rats, in which they affected 39 +/- 7, 44 +/- 5 and 15 +/- 5% of arcuate arterial branches, interlobular arteries and afferent arterioles, respectively. Immunoreactive endothelin-1 was found to accumulate at the level of SB+ lesions. Co-administered with L-NAME, hydralazine (15 mg kg-1 day-1, per os) limited SBP rise to approximately 10 mmHg in both LN and LH rats. As a result, SB+ lesions were rare in LN rats, but were frequent in LH rats. In conclusion, preglomerular SB+ lesions are spontaneously lacking in LH rats. Endogenous nitric oxide production provides protection against vascular barotrauma. Endothelin-1 likely plays an autocrine/paracrine role in vascular lesion formation.

• Authors: D Casellas, N Bouriquet, A Artuso
• Journal: Acta physiologica Scandinavica (Acta Physiol Scand) Vol. 168 Issue 1 Pg. 133-8 (Jan 2000) ISSN: 0001-6772 [Print] England
• PMID: 10691791 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antihypertensive Agents
• Azo Compounds
• Coloring Agents
• Drug Combinations
• Enzyme Inhibitors
• Naphthalenes
• Hydralazine
• Nitric Oxide
• Sudan Black B
• NG-Nitroarginine Methyl Ester

Topics

• Aging (physiology)
• Animals
• Antihypertensive Agents (pharmacology)
• Azo Compounds
• Coloring Agents
• Drug Combinations
• Enzyme Inhibitors (pharmacology)
• Hydralazine (pharmacology)
• Hypertension (complications)
• Kidney Glomerulus (blood supply)
• NG-Nitroarginine Methyl Ester (pharmacology)
• Naphthalenes
• Nitric Oxide (physiology)
• Rats
• Rats, Inbred SHR (anatomy & histology)
• Vascular Diseases (etiology, pathology)