Humoral Response after SARS-CoV-2 mRNA Vaccination in a Cohort of Hemodialysis Patients and Kidney Transplant Recipients.

Background: Kidney transplant recipients and patients receiving hemodialysis are immunocompromised populations that are prioritized for COVID-19 vaccination but were excluded from clinical trials of SARS-CoV-2 mRNA vaccines. Antibody titers and rates of seroconversion after vaccination are lower among patients with CKD and those taking immunosuppressants compared with controls. Data are lacking regarding their humoral response to vaccination to prevent COVID-19.

Blood pressure control in patients with chronic kidney disease according to office and home blood pressures.

Objectives: The aim of this study was to assess blood pressure (BP) control in patients with chronic kidney disease (CKD) according to office and home BP and to assess the prevalence of normal BP, white-coat uncontrolled hypertension (WUCH), masked uncontrolled hypertension (MUCH) and elevated BP.

Methods: Patients with renal failure with or without proteinuria were included in this multicenter observational study. Office BP was first measured by the physician using a self-monitoring BP device (three automatic readings), then by the patient at home (morning and evening) over 3 consecutive days.

Angiotensin IV improves subnormothermic machine perfusion preservation of rat liver graft.

This study aims to determine whether Angiotensin IV (Ang IV) addition to Celsior preservation solution could improve hepatic endothelium function and provide better liver protection during subnormothermic machine preservation (SMP). Two experimental models were used: In the first part of the study, rings isolated from rat hepatic artery were preserved in Celsior solution (6 h, 20 °C) with and without Ang IV (10 M), then, endothelium-dependent relaxation (EDR) and the concentration of acetylcholine inducing half-maximal relaxation of pre-contracted rings (EC50) were measured. Also, in order to investigate the implication of nitric oxide (NO) on EDR, the rings of hepatic artery were incubated with L-NG-nitroarginine metyl ester (L-NAME).

Effects of Institut Georges Lopez-1 and Celsior preservation solutions on liver graft injury.

Aim: To compare Institut Georges Lopez (IGL-1) and Celsior preservation solutions for hepatic endothelium relaxation and liver cold ischemia reperfusion injury (IRI).

Methods: Two experimental models were used. In the first one, acetylcholine-induced endothelium-dependent relaxation (EDR) was measured in isolated ring preparations of rat hepatic arteries preserved or not in IGL-1 or Celsior solutions (24 h at 4 °C).

Candesartan restores pressure-induced vasodilation and prevents skin pressure ulcer formation in diabetic mice.

Background: Angiotensin II type 1 receptor (AT1R) blockers have beneficial effects on neurovascular complications in diabetes and in organ's protection against ischemic episodes. The present study examines whether the AT1R blocker candesartan (1) has a beneficial effect on diabetes-induced alteration of pressure-induced vasodilation (PIV, a cutaneous physiological neurovascular mechanism which could delay the occurrence of tissue ischemia), and (2) could be protective against skin pressure ulcer formation.

Methods: Male Swiss mice aged 5-6 weeks were randomly assigned to four experimental groups.

Erythropoietin restores C-fiber function and prevents pressure ulcer formation in diabetic mice.

Pressure-induced vasodilatation (PIV), a cutaneous physiological neurovascular (C-fiber/endothelium) mechanism, is altered in diabetes and could possibly contribute to pressure ulcer development. We wanted to determine whether recombinant human erythropoietin (rhEPO), which has protective neurovascular effects, could prevent PIV alteration and pressure ulcer formation. We developed a skin pressure ulcer model in mice by applying two magnetic plates to the dorsal skin.

WNK1 regulates vasoconstriction and blood pressure response to α 1-adrenergic stimulation in mice.

Gain-of-function mutations in the human WNK1 (with-no-lysine[K]1) gene are responsible for a monogenic form of arterial hypertension, and WNK1 polymorphisms have been associated with common essential hypertension. The role of WNK1 in renal ionic reabsorption has been established, but no investigation of its possible influence on vascular tone, an essential determinant of blood pressure, has been performed until now. WNK1 complete inactivation in the mouse is embryonically lethal.

Prevention of dementia by antihypertensive drugs: how AT1-receptor-blockers and dihydropyridines better prevent dementia in hypertensive patients than thiazides and ACE-inhibitors.

Our review of cohort studies and clinical trials evaluating antihypertensive drugs in the prevention of cognition decline and all dementia in patients with hypertension indicates that two antihypertensive drug classes have greater protective effects, independent of blood pressure decrease: dihydropyridine calcium-channel blockers as shown in the Syst-Eur trial and angiotensin-AT1 receptor blockers as found in the MOSES and ONTARGET trials. By contrast, diuretics and angiotensin-converting enzyme-inhibitors (ACEIs) prevent dementia only in patients with a stroke history, provided they are combined, and prevent stroke recurrence. A Japanese cohort study and a small trial in patients already suffering from Alzheimer's disease (AD) suggest, however, that the BBB-penetrating ACEI may slow down cognitive decline.

Angiotensin AT1-receptor blockers and cerebrovascular protection: do they actually have a cutting edge over angiotensin-converting enzyme inhibitors?

First, an update of the vascular systemic and tissue renin-angiotensin-aldosterone system is provided to explain how it is regulated at the systemic and tissue levels, and how many angiotensin peptides and receptors can be modulated by the various antihypertensive drugs. Second, experimental data is presented to support the hypothesis that antihypertensive drugs that increase angiotensin II formation, such as diuretics, AT1-receptor blockers and dihydropyridines, may have greater brain anti-ischemic effects than antihypertensive drugs that decrease angiotensin II formation, such as beta-blockers and angiotensin-converting enzyme inhibitors, because they increase activation of angiotensin AT2 and AT4 receptors. Indeed, these trigger brain anti-ischemic mechanisms by favouring cerebral blood flow (angiogenesis and recruitment of pre-existing collateral circulation, specifically in the ischemic brain where AT2 receptors are overexpressed) or by directly increasing neuronal resistance to anoxia.

Protective effect of candesartan in experimental ischemic stroke in the rat mediated by AT2 and AT4 receptors.

Objectives: The contribution of the AT2 and AT4 angiotensin receptors to the protective role of the AT1 receptor blocker candesartan in acute ischemic stroke was investigated.

Methods: Embolic stroke was induced by injection of calibrated microspheres (50 microm) in the right internal carotid in Sprague-Dawley rats.

Results: Inhibition of production of endogenous angiotensins by pretreatment for 24 h with lisinopril significantly increased mortality and infarct volume, whereas candesartan for 24 h reduced blood pressure to the same extent but had no deleterious effect.

Does a change in angiotensin II formation caused by antihypertensive drugs affect the risk of stroke? A meta-analysis of trials according to treatment with potentially different effects on angiotensin II.

Background: Stroke prevention by antihypertensive therapy is believed to be related to the fall in blood pressure (BP). Experimental data have documented that activation of non-AT1 receptors of angiotensin II may exert anti-ischaemic mechanisms in the brain. The present meta-analysis of various randomized clinical trials attempts to relate stroke risk to angiotensin II formation during antihypertensive therapy.

Synergistic protective effects of erythropoietin and olmesartan on ischemic stroke survival and post-stroke memory dysfunctions in the gerbil.

Objectives: Treatment with erythropoietin and AT1 blockers is protective in experimental acute cerebral ischemia, with promising results in pilot clinical studies in human stroke. This paper examines the effects of using both agents as combination therapy in acute ischemic stroke.

Methods: We used the single carotid ligation stroke model in the gerbil.

Inherited sodium avid states.

Several familial forms of hypertension have been identified, in which the mendelian pattern of inheritance indicated that hypertension results from the alteration of a single gene. This short review focuses on those rare monogenic disorders characterized by a low-renin profile. This common feature reflects that the causative mutations responsible for these disorders all result in an excessive sodium reabsorption in the aldosterone-dependent nephron.

Vasoconstrictive effect of angiotensin IV in isolated rat basilar artery independent of AT1 and AT2 receptors.

The effect of angiotensin IV (AngIV) was studied in freshly isolated rat basilar arteries (BAs) perfused at a constant rate. AngIV had no effect on basal BA perfusion pressure, but induced a marked concentration-dependent contraction in vessels precontracted by a 50-mM KCl solution (EC50=44.5+/-16 nM).

The renin-angiotensin systems: evolving pharmacological perspectives for cerebroprotection.

During the last 20 years, the renin-angiotensin system (RAS) has become an increasingly important focus of basic and clinical cardiovascular research. One main conceptual step forward was made with the discovery of a tissue RAS and the understanding of its critical pathophysiological role in atherogenesis and plaque destabilisation. Major effort to find new strategies for blocking the RAS has produced new classes of drugs which were expected to be clinically important in the management of hypertension and heart failure.