Abstract
Primary acute sympathetic activation (PASA) can increase arterial pressure (AP). Under this situation, the kidneys may receive mutually opposing influences from sympathetic activation: a direct anti-diuretic effect via the renal innervation and pressure diuresis. We examined whether PASA would reduce urine output regardless of the AP elevation. We also examined the impact of renal denervation (RDN) on urine output during PASA. The experiment was performed on rats 3 to 9 days after unilateral RDN (n = 10). Under anesthesia, systemic sympathetic nerve activity (SNA) was varied over a wide range via the carotid sinus baroreflex. The slope of urine flow versus SNA was positive (0.252 ± 0.052 μL·min−1·kg−1· %−1) on the intact side, and it was greater on the denervated side (0.331 ± 0.069 μL·min−1·kg−1· %−1, P < 0.05). In conclusion, urine output change was an effect of elevated AP during PASA. Nevertheless, RDN was able to augment pressure diuresis during PASA.
Highlights
The arterial baroreflex system is an essential negative feedback system that stabilizes arterial pressure (AP) against pressure fluctuations. This system may be analyzed by dividing it into two principal subsystems [1]: the neural arc subsystem that describes the relationship between a baroreceptor pressure input and efferent sympathetic nerve activity (SNA), and the peripheral arc subsystem that describes the relationship between SNA and AP
When AP is decreased by an exogenous perturbation, SNA increases via the negative feedback through the neural arc and counteracts the pressure decrease (Fig. 1a)
NUF increased as SNA increased (Fig. 3e), which suggests that the urine output change was not a cause for the AP elevation during Primary acute sympathetic activation (PASA)
Summary
The arterial baroreflex system is an essential negative feedback system that stabilizes arterial pressure (AP) against pressure fluctuations This system may be analyzed by dividing it into two principal subsystems [1]: the neural arc subsystem that describes the relationship between a baroreceptor pressure input and efferent sympathetic nerve activity (SNA), and the peripheral arc subsystem that describes the relationship between SNA and AP. When AP is decreased by an exogenous perturbation, SNA increases via the negative feedback through the neural arc and counteracts the pressure decrease (Fig. 1a). In this situation, the AP reduction and the reflex sympathetic activation act synergistically to reduce urine output because the AP reduction decreases the renal. To analyze changes in urine output during PASA, we employed a baroreflex open-loop procedure in anesthetized rats
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
