Effects of perindopril on cardiovascular remodeling

Management of hypertension in patients with cardiac disease: use of renin-angiotensin blocking agents

Inhibition of renin-angiotensin system (RAS) activity using angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (ARBs) is beneficial in patient populations with left ventricular dysfunction or systolic heart failure (HF) and other forms of heart disease. In high-risk patients with coronary heart disease (CHD), treatment with these agents reduces the mortality rate and improves secondary outcomes. Individuals with stable CHD who are at lower risk benefit less from treatment. RAS inhibition also provides some clinical benefit to patients with diastolic HF and preserved left ventricular function. Left ventricular hypertrophy (LVH) is a strong predictor of cardiovascular events and all-cause mortality in patients with hypertension. Treatment with an ARB reduces the risk for adverse cardiovascular outcomes in patients with hypertension and LVH. The benefits correlate with regression of LVH, and the effect is independent of the degree of blood pressure lowering. Finally, studies indicate that a history of hypertension in patients who have not had a myocardial infarction (MI) increases the risk for HF after MI; the risk is decreased in patients with hypertension who receive treatment with a RAS inhibitor.

Differential expression of angiotensin receptors in human cutaneous wound healing

BACKGROUND

Angiotensin AT1 and AT2 receptors are expressed in human skin. Furthermore, AT2 receptors have been reported to be upregulated during tissue repair and remodelling in various noncutaneous human tissues.

OBJECTIVES

Detection of alterations in angiotensin II receptor expression during wound healing in human skin.

METHODS

Three models were employed. (i) Primary human keratinocytes were razor scraped in culture flasks and alterations in the expression of angiotensin receptor mRNA determined by semiquantitative reverse transcription-polymerase chain reaction for 1-12 h thereafter. (ii) Early wound healing (48 h after cutting) was studied in punch biopsies from human skin ex vivo by means of immunohistochemical staining using polyclonal antibodies against the AT1 or AT2 receptor. (iii) In vivo wound healing was studied in sections of human cutaneous scars by immunohistochemistry to determine receptor expression early (2 days) and late (2 weeks-3 months) after surgery.

RESULTS

In all experimental settings, an upregulation of both receptor subtypes was noticed after wounding. Immunohistochemically stained skin sections showed a stronger expression of AT2 than of AT1 receptors within the area of scarring. Enhanced receptor expression was detectable as early as 24 h after injury and lasted for up to 3 months.

CONCLUSIONS

From these data, we conclude that angiotensin AT1 and AT2 receptors are upregulated in human cutaneous wounds, giving further support to the concept that angiotensin II plays a role even at an early stage during cutaneous wound healing.

Mechanisms of target organ damage caused by hypertension: therapeutic potential

Hypertension is a major risk factor for cardiovascular mortality and morbidity through its effects on target organs like the brain, heart, and kidney. Structural alterations in the microcirculation form a major link between hypertension and target organ damage. In this review, we describe damages related to hypertension in these target organs and the mechanisms involved in the pathogenesis of hypertension-induced cardiovascular diseases such as dementia, cardiac ischemia and remodeling, or nephropathy. We also focus on the therapeutical potential on the basis of such mechanisms. Several antihypertensive agents like diuretics, angiotensin converting enzyme (ACE) inhibitors, angiotensin II (Ang II) receptor antagonists, beta-blockers, or calcium channel blockers (CCBs) have been shown to reduce effectively hypertension associated cardiovascular events and to improve end organ damage. More recently, aldosterone antagonism has also shown beneficial effects. Part of the favorable effects of these agents is due to blood pressure lowering as such. Other mechanisms such as oxidative stress, inflammation, or endothelial dysfunction have appeared to play a key role in the pathogenesis of target organ damage and therefore represent another important pathway for therapy. In this review, we discuss the different therapeutic approaches aiming at reducing cardiovascular events and damages induced by hypertension.

Angiotensin receptor blockade and arterial compliance in chronic kidney disease: a pilot study

BACKGROUND

Almost 20 million people in the US have chronic kidney disease (CKD). Cardiovascular disease and arterial wall abnormalities are common in this population. Because angiotensin II may have adverse effects on the arterial wall, we hypothesized that an angiotensin receptor blocker (ARB) would improve arterial compliance as compared with placebo in subjects with CKD.

METHODS

We performed a double-blinded, placebo-controlled pilot study in which 25 subjects with stages 2 or 3 CKD and proteinuria <1 g were randomized to either the ARB, eprosartan, or placebo and titrated to achieve a goal blood pressure (BP) <130/85 mm Hg. Arterial compliance was measured at baseline and at 8 weeks.

RESULTS

Baseline characteristics were similar between the groups and included mean estimated glomerular filtration rate 63 +/- 14 ml/min/1.73 m(2), heart rate 76 +/- 10 beats/min, BP 142 +/- 12/81 +/- 8 mm Hg, 64% diabetic, 44% male, and 40% white, though subjects in the eprosartan group were younger (60 +/- 12 vs. 70 +/- 6 years, p = 0.01). There were no significant differences between the groups in large or small artery compliance measurements either at baseline or at 8 weeks, but there was a statistically significant improvement from baseline in small artery compliance in the eprosartan group (from median 2.5 ml/mm Hg x 100 [90% CI (1.1, 4.7)] to 4.0 ml/mm Hg x 100 [90% CI (1.9, 6.7)] (p = 0.01)) not seen in the placebo group.

CONCLUSION

Use of an ARB to achieve recommended BP is associated with improved small artery compliance in people with CKD, though larger studies are needed to confirm these findings.