In vivo investigation of homocysteine metabolism to polyamines by high-resolution accurate mass spectrometry and stable isotope labeling.

Polyamines are essential polycations, playing important roles in mammalian physiology. Theoretically, the involvement of homocysteine in polyamine synthesis via S-adenosylmethionine is possible; however, to our knowledge, it has not been established experimentally. Here, we propose an original approach for investigation of homocysteine metabolites in an animal model.

Interaction of endothelin with renal nerves modulates kidney function in spontaneously hypertensive rats.

Background And Methods: We investigated kidney function, renal endothelin-1 concentration, prepro-endothelin-1 mRNA as well as endothelin receptor A and B mRNA expression and receptor properties in normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) with intact renal nerves and 7 days after renal denervation. In addition, responses of renal function to the non-selective ETA/ETB receptor blocker bosentan (10 mg/kg i.v.

Impaired response of the denervated kidney to endothelin receptor blockade in normotensive and spontaneously hypertensive rats.

Background: As yet, there are only limited data available on the exact role of endothelin (ET) acting through endothelin-A (ETA) receptors in renal sodium and water regulation and the potential functional implications of an interaction of the renal ET system with renal nerves in normotensive and spontaneously hypertensive rats.

Methods: Experiments were carried out in 64 male conscious spontaneously hypertensive rats and in 56 normotensive Wistar-Kyoto (WKY) rats. Bilateral renal denervation (BRD) was performed in 32 spontaneously hypertensive rats and 28 WKY rats 7 days before the experiments.

Renal and cardiovascular effects of renal denervation in conscious rats after adenosine administration and nitric oxide synthase inhibition.

The role of renal nerves on renal and cardiovascular responses to adenosine administration and/or acute NO synthase inhibition was investigated. Conscious male Wistar rats with implanted catheters in femoral artery for blood pressure registration, femoral vein for drug infusion and bladder for urine collection were used. Adenosine was applied i.