Afferent innervation of the ischemic kidney contributes to renal dysfunction in renovascular hypertensive rats

• Published in: Pflügers Archiv 2020-03, Vol.472 (3), p.325-334
• Main Authors: Lopes, Nathalia R., Milanez, Maycon I. O., Martins, Beatriz S., Veiga, Amanda C., Ferreira, Giovanna R., Gomes, Guiomar N., Girardi, Adriana C., Carvalho, Polliane M., Nogueira, Fernando N., Campos, Ruy R., Bergamaschi, Cássia T., Nishi, Erika E.
• Format: Article
• Language: English
• Subjects: Ablation; Afferent Pathways - physiopathology; Animals; Baroreflex - physiology; Biomedical and Life Sciences; Biomedicine; Blood pressure; Blood Pressure - physiology; Capsaicin; Cell Biology; Denervation; Fibers; Human Physiology; Hypertension; Hypertension, Renovascular - physiopathology; Innervation; Integrative Physiology; Ischemia; Ischemia - physiopathology; Kidney - physiopathology; Kidney Diseases - physiopathology; Kidneys; Male; Molecular Medicine; Neurosciences; Paraventricular Hypothalamic Nucleus - physiopathology; Proteinuria; Rats; Rats, Wistar; Reactive oxygen species; Receptors; Renal artery; Renal function; Renal plexus; Sensory neurons; Sympathetic nerves; Sympathetic Nervous System - physiopathology
• ISSN: 0031-6768; 1432-2013
• DOI: 10.1007/s00424-019-02346-4

The ablation of renal nerves, by destroying both the sympathetic and afferent fibers, has been shown to be effective in lowering blood pressure in resistant hypertensive patients. However, experimental studies have reported that the removal of sympathetic fibers may lead to side effects, such as the impairment of compensatory cardiorenal responses during a hemodynamic challenge. In the present study, we evaluated the effects of the selective removal of renal afferent fibers on arterial hypertension, renal sympathetic nerve activity, and renal changes in a model of renovascular hypertension. After 4 weeks of clipping the left renal artery, afferent renal denervation (ARD) was performed by exposing the left renal nerve to a 33 mM capsaicin solution for 15 min. After 2 weeks of ARD, we found reduced MAP (~ 18%) and sympathoexcitation to both the ischemic and contralateral kidneys in the hypertensive group. Moreover, a reduction in reactive oxygen species was observed in the ischemic (76%) and contralateral (27%) kidneys in the 2K1C group. In addition, ARD normalized renal function markers and proteinuria and podocin in the contralateral kidney. Taken altogether, we show that the selective removal of afferent fibers is an effective method to reduce MAP and improve renal changes without compromising the function of renal sympathetic fibers in the 2K1C model. Renal afferent nerves may be a new target in neurogenic hypertension and renal dysfunction.