AIMS: Transient receptor potential vanilloid 2 (TRPV2) channels are expressed in both smooth muscle and endothelial cells and participate in vascular mechanotransduction and sensing of high temperatures and lipids. Nevertheless, the impact of TRPV2 channel activation by agonists on the coordinated and cell-type specific modulation of vasoreactivity is unknown. MAIN METHODS: Aorta from 2- to 4-months-old male Oncins France 1 mice was dissected and mounted in tissue baths for isometric tension measurements. TRPV2 channel expression was assessed by immunofluorescence and western blot in mice aortas and in cultured A7r5 rat aortic smooth muscle cells. KEY FINDINGS: TRPV2 channels were expressed in all three mouse aorta layers. Activation of TRPV2 channels with probenecid evoked endothelium-dependent relaxations through a mechanism that involved activation of smooth muscle Kir and Kv channels. In addition, TRPV2 channel inhibition with tranilast increased endothelium-independent relaxations to probenecid and this effect was abrogated by the KATP channel blocker glibenclamide, revealing that smooth muscle TRPV2 channels induce negative feedback on probenecid relaxations mediated via KATP channel inhibition. Exposure to the NO donor sodium nitroprusside increased TRPV2 channel translocation to the plasma membrane in cultured smooth muscle cells and enhanced negative feedback on probenecid relaxations. SIGNIFICANCE: In conclusion, we present the first evidence that TRPV2 channels may modulate vascular tone through a balance of opposed inputs from the endothelium and the smooth muscle leading to net vasodilation. The fact that TRPV2 channel-induced activity can be amplified by NO emphasizes the pathophysiological relevance of these findings.
Endothelial Cells , Probenecid , Mice , Rats , Male , Animals , Probenecid/pharmacology , Mechanotransduction, Cellular , Aorta/metabolism , Vasodilation , Adenosine Triphosphate/metabolism , Endothelium, Vascular/physiology
Resumen Las infecciones parasitarias intestinales son una de las mayores dificultades socioeconómicas y médicas de todo el mundo. El objetivo de esta investigación fue determinar la prevalencia de parásitos intestinales en niños y su asociación a prácticas de higiene y crianza de animales. La investigación fue observacional, básica, analítica y transversal. La población en estudio estuvo conformada de 542 niños de educación primaria del distrito de Tamburco, Perú. Se recolectaron muestras fecales de 225 niños de ambos sexos. Dichas muestras fueron analizadas con la técnica directa con lugol y solución salina fisiológica. El análisis cuantitativo de Kato-Katz se desarrolló en el laboratorio de la Micro Red de Salud Micaela Bastidas, en Tamburco. Se efectuaron las pruebas de chi-cuadrado de Pearson, odds ratio e intervalos de confianza con niveles de confianza de 95 % mediante el programa SPSS 23. Asimismo, se realizó un análisis de regresión logística multivariada. La prevalencia de parásitos intestinales en los niños fue del 63,6 % (143/225; IC 95 %=57,1-70,1). Los niños que no se lavan las manos antes de comer tuvieron mayor riesgo de infección con Blastocystis sp. (OR=20,8), Entamoeba coli (OR=16,9) y Giardia lamblia (OR=6,2) (p < 0,01). Además, los niños que caminan descalzos tuvieron 2,1 veces más riesgo de infectarse con Blastocystis sp. (p < 0,05). En conclusión, la prevalencia de parásitos intestinales en los niños de Tamburco fue alta y estuvo asociada con los hábitos de no lavarse las manos antes de comer y caminar descalzos.
Abstract Intestinal parasitic infections are one of the greatest socioeconomic and medical difficulties worldwide. The objective of this research was to determine the prevalence of intestinal parasites in children and their association with hygiene and animal husbandry practices. The research was observational, basic, analytical and cross-sectional. The study population consisted of 542 primary school children from the district of Tamburco, Peru. Fecal samples were collected from 225 children of both sexes. These samples were analyzed using the direct technique with lugol and physiological saline solution. The quantitative Kato-Katz analysis was performed in the laboratory of the Micro Red de Salud Micaela Bastidas, in Tamburco. Pearson's chi-square tests, odds ratios and confidence intervals with confidence levels of 95% were performed using SPSS 23 software. The prevalence of intestinal parasites in children was 63.6% (143/225; 95% CI=57.1-70.1). Children who did not wash their hands before eating had a higher risk of infection with Blastocystis sp. (OR=20.8), Entamoeba coli (OR=16.9) and Giardia lamblia (OR=6.2) (p < 0.01). In addition, children walking barefoot were 2.1 times more at risk of becoming infected with Blastocystis sp. (p < 0.05). In conclusion, the prevalence of intestinal parasites in Tamburco children was high and was associated with the habits of not washing hands before eating and walking barefoot.
