[Essential hypertension in children--risk factors and target organ damage].

Unlabelled: Regarding that systemic hypertension is an important condition in childhood, we try to clarify existing data about this pathology.

Material And Methods: The aim of our study was to evaluate the incident cases of essential hypertension in children admitted during a four years period in the Children Hospital "Sf. Maria" Iaşi, Romania.

[Relevance of L-type calcium channels for the non-genomic effects of estradiol and aldosterone upon contractile activity in isolated arteries].

Unlabelled: Non-genomic vascular effects of steroids are incompletely understood, despite progress made regarding some aspects, such as the mechanism of endothelium-dependent relaxation by estrogens.

Aim: To investigate the involvement of certain mechanisms in the rapid, non-genomic effects of estradiol (EST) and aldosterone (ALD) on endothelium-dependent and -independent vasomotor responses.

Material And Methods: Isometric myography of rings from aorta, mesenteric arch, and first order mesenteric branches isolated from male Wistar rats was used.

The importance of EDHF in endothelium-dependent relaxation increases distally in mesenteric arteries depending upon the contracting agent.

Aim: The importance of endothelium-derived hyperpolarizing factor (EDHF) in endothelium-dependent relaxation (EDR) is influenced by multiple factors, including vascular territory and caliber, pre-existing tone and its determining factors.

Method: Using isometric myography we noticed that in rat mesenteric resistance arteries (RMA2; 2nd order branches) EDHF-mediated relaxation is increased when precontraction is induced by prostaglandin F2 (PGF) compared to phenylephrine (PHE) and we investigated the participation of certain K channels. Here we extend the study on more proximal vascular fragments; from mesenteric arcade and from 1st order branches.

Relaxation and polarization of precontracted rat aortic smooth muscle by sodium nitrite and an L-type channel blocker.

Unlabelled: Membrane potential (MP) is essential for smooth muscle (SM) contraction, mainly by determining the activity of L-type Ca2+ channels (Ca(L)). Although a widely used SM model, there are few electrophysiology studies in rat aorta.

Aim: We investigated the mechanism of SM relaxation induced by NaNO2 in comparison with a Ca(L) blocker.