Hypertension and nephrology

[Fenestration of endothelium of juxtaglomerular arteriole]

ROSIVALL László

FEBRUARY 20, 2014

Hypertension and nephrology - 2014;18(01-02)

[For the first time, we demonstrated the fenestration in the endothelium of the distal portion of renal afferent arteriole (AA), which is unusual among high pressure vessels. The fenestrae are co-localized with renin producing granular epithelioid cells; this arrangement makes it likely that the relatively large renin molecules may use this path to enter into the plasma. We also demonstrated that the length and area of this fenestrated segment 1) correlates with the activity of the renin-angiotensin system (RAS), 2) may change by age, in response to some stimuli such as thirst and in some diseases, 3) allows filtration of fluid prior to the glomerular filtration, which can be as high as about 30% of GFR. This morphology and the high filtration volume in AA is one of the most striking observations of renal microcirculation, and question several basic renal physiological issues.]

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