Abstract: FR-PO380
The Positive Effect of Renal Denervation Persists even Through Regrowth of Afferent Axons Improving Renal Afferent Nerve Activity During High Sodium Intake in Rats
Session Information
- Hypertension and CVD: Basic
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Hypertension and CVD
- 1601 Hypertension and CVD: Basic
Authors
- Rodionova, Kristina, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Ditting, Tilmann, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Cordasic, Nada, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Hilgers, Karl F., Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Linz, Peter, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Schiffer, Mario, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Amann, Kerstin U., Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
- Veelken, Roland, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Erlangen, Bayern, Germany
Background
Previous work of ours suggests that pathologically decreased sensitivity of renal afferent neurons (reduced number of highly active tonic neurons) due to high salt diet is normalized 1 wk after renal denervation (DNX). Now we tested the hypothesis that normalized sensitivity of renal neurons persists after DNX even through regrowth of afferent axons after 12 wk. This morphological regrowth of afferent nerves 12wk after renal DNX (postDNX) was shown in a previous publication (DOI: 10.1152/ajpregu.00227.2014).
Methods
6 male Sprague Dawley (SD) rats were put on high salt diet (HS; 8% NaCl) for 10 days. In another group of 12 rats on high salt diet (HS) left kidneys were denervated (postDNX) 12 weeks prior to examination. Rats on standard diet 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
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). Denervation of the left kidney in rats on high salt diet (HS-DNX) led to a recovery of afferent renal DRG neurons after 1 wk (42% tonic neurons on HS vs. 72% tonic neurons on HS+DNX). Even 12 weeks after renal denervation this regained electrophysiological property of tonic firing persists (42% tonic neurons on HS vs. 69% tonic neurons on HS-postDNX, p<0.05, z-test).
Conclusion
The reduced proportion of highly active tonic neurons increased 1 wk after renal denervation to control levels. Even 12 weeks after renal denervation, this effect of renal denervation persisted, and the sensitivity of renal neurons to electrical stimuli did not change despite high-salt diet. Hence, the positive effects of renal denervation persisted even through the regrowth of renal afferent axons to the kidney.