Abstract P410: A Novel Method For The Analysis Of Renal Sympathetic Nerve Activity From Multi-fiber Nerve Recordings

• Published in: Hypertension (Dallas, Tex. 1979) Tex. 1979), 2023-09, Vol.80 (Suppl_1)
• Main Authors: Rodionova, Kristina, Veelken, Roland, Cordasic, Nada, Hilgers, Karl F, Schmieder, Roland E, Schiffer, Mario, Amann, Kerstin, Ditting, Tilmann
• Format: Article
• Language: English
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/hyp.80.suppl_1.P410

Abstract only Introduction: Measurement of renal sympathetic nerve activity (RSNA) via bipolar electrodes from multi-fiber preparations in various species has been used for decades in the context of autonomic regulation research. Traditionally, raw neurograms are usually integrated over short time intervals and this approach works perfectly for the analysis of dynamic RSNA changes due to acute intervention. However, comparability of baseline activities between groups is limited. We present a novel analysis method, based on the raw neurogram sampled at rate of 25 kHz. Material and methods: For RSNA-burst analysis a software based programmable algorithm was used. Continuous activities longer than three single spikes (i.e., >8ms) were defined as bursts, followed by silent periods with some single spikes. Approximately 10.000 bursts/rat were analyzed and burst amplitude, burst duration, burst area (i.e., duration integral), as well as the burst frequencies were analyzed. Results: In rats with myocardial infarction (n=11) we found no difference in integrated baseline RSNA as compared to controls ((n=10). However, the new method revealed higher higher burst rate per cardiac cycle [CC] (2.65 ± 0.39 vs. 1.61 ± 0.38 bursts/CC; P