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bioRxiv · 10.1101/2022.09.19.508507

The assessment of cortical hemodynamical responses induced by tubuloglomerular feedback using in vivo imaging

Lee, B. S.·Postnov, D. D.·Sorensen, C. M.·Sosnovtseva, O.
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Abstract

The tubuloglomerular feedback (TGF) mechanism is crucial in modulating renal hemodynamics and glomerular filtration rate in individual nephrons. Our study aimed to evaluate the TGF-induced vascular responses by comparing the effects of two transport inhibitors with different sites and mechanisms of action. We assessed cortical hemodynamics with high-resolution laser speckle contrast imaging, which enabled the evaluation of blood flow individual micro-vessels and analysis of their dynamical patterns in the time-frequency domain. We demonstrated that a systemic administration of a loop diuretic abolishes TGF-mediated hemodynamic responses. Furthermore, we showed that the local microcirculatory blood flow decreased, and the TGF reset in response to reduced proximal reabsorption elicited by systemic administration of a sodium-glucose co-transporter 2 inhibitor, phlorizin.

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Lee, B. S., Postnov, D. D., Sorensen, C. M., Sosnovtseva, O.. 2022-09-19. The assessment of cortical hemodynamical responses induced by tubuloglomerular feedback using in vivo imaging. https://doi.org/10.1101/2022.09.19.508507

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