title: Decoding intravesical pressure from local field potentials in rat lumbosacral spinal cord.
abstract: Chronic monitoring of intravesical pressure is required to detect the onset of intravesical hypertension and the progression of a more severe condition. Recent reports demonstrate the bladder state can be monitored from the spiking activity of the dorsal root ganglia or lumbosacral spinal cord. However, one of the most serious challenges for these methods is the difficulty of sustained spike signal acquisition due to the high-electrode-location-sensitivity of spikes or neuro-degeneration. Alternatively, it has been demonstrated that local field potential recordings are less affected by encapsulation reactions or electrode location changes. Here, we hypothesized that local field potential (LFP) from the lumbosacral dorsal horn may provide information concerning the intravesical pressure. LFP and spike activities were simultaneously recorded from the lumbosacral spinal cord of anesthetized rats during bladder filling. The results show that the LFP activities carry significant information about intravesical pressure along with spiking activities. Importantly, the intravesical pressure is decoded from the power in high-frequency bands (83.9-256 Hz) with a substantial performance similar to that of the spike train decoding. These findings demonstrate that high-frequency LFP activity can be an alternative intravesical pressure monitoring signal, which could lead to a proper closed loop system for urinary control.
authors.affiliation: Department of Biomedical Engineering, College of Health Science, Yonsei University, Wonju 26493, Korea. BK21 Plus Transformative Training Program for Creative Mechanical Engineers, Seoul National University, Seoul 08826, Korea.
authors.forename: Changkyun
authors.initials: C
authors.lastname: Im
authors.forename: Hae Yong
authors.initials: HY
authors.lastname: Park
authors.forename: Chin Su
authors.initials: CS
authors.lastname: Koh
authors.forename: Sang Baek
authors.initials: SB
authors.lastname: Ryu
authors.forename: In Seok
authors.initials: IS
authors.lastname: Seo
authors.forename: Yong Jung
authors.initials: YJ
authors.lastname: Kim
authors.forename: Kyung Hwan
authors.initials: KH
authors.lastname: Kim
authors.forename: Hyung-Cheul
authors.initials: HC
authors.lastname: Shin
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000465:Algorithms; D000758:Anesthesia; D000818:Animals; D004566:Electrodes; D005260:Female; D005727:Ganglia, Spinal / Q000502:physiology; D008161:Lumbosacral Region / Q000502:physiology*; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods*; D058117:Neural Prostheses; D011312:Pressure; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology*; D001743:Urinary Bladder / Q000294:innervation / Q000502:physiology*