Abstract: PO1817
Renal Denervation Improves Renal Afferent Nerve Activity After High Sodium Intake
Session Information
- Hypertension and CVD: Mechanisms
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Hypertension and CVD
- 1403 Hypertension and CVD: Mechanisms
Authors
- Rodionova, Kristina, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Ditting, Tilmann, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Rafii-Tabrizi, Salman, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Döllner, Johannes, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Hilgers, Karl F., Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Linz, Peter, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Ott, Christian, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Schmieder, Roland E., Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Schiffer, Mario, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
- Amann, Kerstin U., Universitätsklinikum Erlangen, Abteilung für Nephropathologie, Erlangen, Germany
- Veelken, Roland, Universitatsklinikum Erlangen Medizinische Klinik 4 Nephrologie und Hypertensiologie, Erlangen, Bayern, Germany
Background
Previous work of ours suggests that the sensitivity of renal afferent neurons is decreased under pathological conditions. Here we tested the hypothesis that pathologically decreased sensitivity of renal afferent neurons due to high salt diet is normalized after renal denervation.
Methods
6 male Sprague Dawley (SD) rats were put on high salt diet (HS; 8% NaCl) for 10 days. In another group of 18 rats on high salt diet (HS) left kidney were deneravated (DNX) 7 days prior to examination. Rats on standard diet with and without DNX (10 and 7 SD rats) were used as controls. Harvested dorsal root ganglion neurons (DRG Th11-L2) with renal afferents were investigated in primary neuronal cell culture using current clamp mode to assess action potential generation during current injection and to characterize neurons as tonic highly active and phasic less active neurons. Results are mean±SEM.
Results
In renal neurons from rats on HS the relation of tonic to phasic neurons shifted towards less active phasic units (62% tonic neurons in control vs. 42% on HS, p<0.05, z-test). Further, neurons from rats on HS exhibited decreased action potential production upon stimulation (controls 14.8+/-0.9 APs/600ms vs. HS 12.1+/-0.8 APs/600ms, p<0.05, t-test). Denervation (DNX) of the left kidney in rats on high salt diet (HS-DNX) led to a recovery of afferent renal DRG neurons. They regained their ability to generate action potentials as in controls (high salt diet 12.1+/-0.8 APs/600ms vs. HS-DNX 14.8+/-0.7 APs/600ms, p<0.05, t-test) and their electrophysiological property of tonic firing (42% tonic neurons in HS vs. 71% HS-DNX, p<0.05, z-test).
Conclusion
In rats on high salt (HS) diet the in vitro proportion of highly active tonic neurons with renal afferents decreased at the expense of less active phasic neurons. Furthermore, their firing rate decreased due to HS. These HS effects could be abolished by renal denervation (DNX). Whether DNX in vivo would be able to reduce HS induced sympathetic nerve activity increases remains to be determined.