Catheter-based induction of renal ischemia/reperfusion in swine: description of an experimental model

Abstract

Several techniques to induce renal ischemia have been proposed: clamp, PVA particles, and catheter‐balloon. We report the development of a controlled, single‐insult model of unilateral renal ischemia/reperfusion (I/R) without contralateral nephrectomy, using a suitable model, the pig. This is a balloon‐catheter‐based model using a percutaneous, interventional radiology procedure. One angioplasty balloon‐catheter was placed into the right renal artery and inflated for 120 min and reperfusion over 24 h. Serial serums were sampled from the inferior vena cava and urine was directly sampled from the bladder throughout the experiment, and both kidneys were excised after 24 h of reperfusion. Analyses of renal structure and function were performed by hematoxylin–eosin/periodic Acid‐Schiff, serum creatinine (SCr), blood urea nitrogen (BUN), fractional excretion of ions, and glucose, SDS‐PAGE analysis of urinary proteins, and serum neutrophil gelatinase‐associated lipocalin (NGAL). Total nitrated protein was quantified to characterize oxidative stress. Acute tubular necrosis (ATN) was identified in every animal, but only two animals showed levels of SCr above 150% of baseline values. As expected, I/R increased SCr and BUN. Fractional sodium, potassium, chloride, and bicarbonate excretion were modulated during ischemia. Serum‐nitrated proteins and NGAL had two profiles: decreased with ischemia and increased after reperfusion. This decline was associated with increased protein excretion during ischemia and early reperfusion. Altogether, these data show that the renal I/R model can be performed by percutaneous approach in the swine model. This is a suitable translational model to study new early renal ischemic biomarkers and pathophysiological mechanisms in renal ischemia.

Developing imidazoles as CEST MRI pH sensors

“…HPLC purifications were performed using 18C columns (19 mm × 250 mm, Waters Atlantis) at 10 mL/min flow rate of water-acetonitrile eluent, unless specified otherwise. 1 H and 13 C NMR spectra were recorded on a 400 MHz spectrometer. The chemical shifts are reported as δ values (ppm) relative to the water signal in D 2 O. High-resolution mass spectral analyses were performed using the electrospray ionization (ESI) method.…”

“…After all of the solvent was removed under vacuum, Compound 6 was purified by HPLC as a light yellow powder, 300 mg, yield 43%. 1…”

Uricemia in juvenile pigs model: effect of nephrectomy and potassium oxonate

“…Swine model more accurately reflects the changes occurring in humans, not only because of the anatomical similarities but also due to a metabolic rate closer to humans when compared to rodents (Swindle et al, 2012). Therefore, studies of metabolomics and proteomics with this model is a critical step in understanding physiology, pathophysiology and the development of therapies in both humans and animals (Malagrino et al, 2014). In our previous study we investigated the extra-renal elimination of uric acid via the intestine in a healthy pig model and the effect of oral uricase therapy on plasma uric acid concentrations in nephrectomized pigs with induced hyperuricemia (Szczurek et al, 2017).…”

Perfil proteômico da lesão renal aguda induzida por isquemia e reperfusão

“…Em modelos animais de isquemia têm-se observado aumento de proteínas nitradas na superfície de células epiteliais dentro do lúmen celular do rim após 6 e 24h de reperfusão (Chiao et al 1997;Walker et al 2000), bem como um aumento na concentração de proteínas nitradas totais no soro e excretadas na urina logo após a isquemia (Malagrino et al 2014 Em pacientes com LRA, a nitração da tirosina no soro aumentou com a gravidade da doença e foi independentemente associada à mortalidade desses pacientes (Qian et al 2013). Esse aumento também foi observado nos estágios iniciais da DRC (Mitrogianni et al 2004;Matsuyama et al 2009), que retornaram aos níveis basais após o transplante renal (Simmons et al 2005;Galli 2007) Atualmente tem-se estudado avaliar a TFG também pela medida indireta da cistatina c urinária em casos em que não há proteinúria (Charlton et al 2014).…”

“…Animal model experiments were conducted according to Malagrino and collaborators [9]. Briefly, five female pigs (Sus scrofa domesticus 15-20 kg) were submitted to unilateral renal I/R.…”