Losartan attenuates vascular remodeling of the aorta in spontaneously hypertensive rats and the underlying mechanism.

Abstract

OBJECTIVE:

To determine the effect of losartan on vascular remodeling and the underlying mechanism in spontaneously hypertensive rats(SHR).

METHODS:

SHR of 12 weeks old were given losartan orally [0, 15, 30 mg/(kg.d), n=12]. The tail arterial pressure was measured every week. Eight weeks later, the pathological changes and p22(phox) expression in the thoracic aorta, the activity of catalase (CAT), the contents of H(2)O(2) and Ang II in the plasma were evaluated.

RESULTS:

Blood pressure was increased in the SHR accompanied by the thickened wall and increased p22(phox) expression in the thoracic aorta. The plasma levels of H(2)O(2) and Ang II were elevated while the CAT level was decreased in the SHR. Administration of losartan reversed the thickened wall and increased the CAT activity concomitantly with the decreased plasma levels of H(2)O(2) and p22(phox) expression in the SHR. The plasma level of Ang II increased after the losartan treatment.

CONCLUSION:

Oxidative stress induces the vascular remodeling of the aorta in the SHR. Losartan can reverse the vascular remodeling through down-regulating p22(phox) expression and inhibiting the oxidative stress.

• Authors: Fangxiong Li, Ruizheng Shi, Meichun Liao, Jianzhe Li, Shixun Li, Wei Pan, Tianlun Yang, Guogang Zhang
• Journal: Zhong nan da xue xue bao. Yi xue ban = Journal of Central South University. Medical sciences (Zhong Nan Da Xue Xue Bao Yi Xue Ban) Vol. 35 Issue 8 Pg. 807-13 (Aug 2010) ISSN: 1672-7347 [Print] China
• PMID: 20818072 (Publication Type: Journal Article)

Chemical References

• Antihypertensive Agents
• Angiotensin II
• Hydrogen Peroxide
• Catalase
• NADPH Oxidases
• Cyba protein, rat
• Losartan

Topics

• Angiotensin II (blood)
• Animals
• Antihypertensive Agents (pharmacology, therapeutic use)
• Aorta (pathology, physiopathology)
• Catalase (metabolism)
• Hydrogen Peroxide (blood)
• Hypertension (drug therapy, pathology, physiopathology)
• Losartan (pharmacology, therapeutic use)
• Male
• NADPH Oxidases (metabolism)
• Oxidative Stress (drug effects)
• Rats
• Rats, Inbred SHR
• Rats, Inbred WKY