Frequency-Domain Analysis Links Autonomic Disruption to Renal Autoregulatory Failure after Spinal Cord Injury
Angela Tsang1, Gagandeep Kaur2, Veronica J Tom3
1Department of Electrical, Computer and Systems Engineering, Case Western Reserve University School of Engineering, Cleveland, OH 44106.
Biorxiv : the Preprint Server for Biology
|July 10, 2026
Summary
High spinal cord injury (SCI) disrupts kidney blood flow control, impairing autoregulation and increasing vulnerability. Low SCI preserves kidney function and allows recovery over time, highlighting injury level's importance.
Area of Science:
- Cardiovascular Physiology
- Neurotrauma
- Renal Autoregulation
Background:
- Spinal cord injury (SCI) disrupts autonomic pathways, causing blood pressure instability and secondary organ injury.
- The kidney, reliant on precise blood flow regulation, is particularly vulnerable to SCI-induced autonomic dysfunction.
- The impact of SCI level and chronicity on dynamic renal autoregulation remains unclear.
Purpose of the Study:
- To investigate how high- and low-thoracic SCI affect renal hemodynamic control and dynamic renal autoregulation.
- To determine the influence of injury chronicity (acute vs. chronic) on these renal vascular responses.
- To elucidate the mechanisms underlying renal dysfunction following SCI.
Main Methods:
- In vivo recordings of blood pressure and renal blood flow (RBF) in female mice following high (T3) or low (T10) thoracic SCI.
- Assessment of hemodynamics at baseline and during norepinephrine-induced sympathetic stimulation at 24 hours and 4 weeks post-injury.
- Application of time-domain and frequency-domain analyses to quantify blood pressure recovery and resolve myogenic and sympathetic contributions to RBF regulation.
Main Results:
- High-thoracic SCI significantly disrupted renal vascular responses, causing paradoxical RBF increases during hypertension and sustained reductions in RBF activity.
- Impairments in renal autoregulation were more pronounced in the chronic phase after high-thoracic SCI, indicating loss of dynamic control.
- Low-thoracic SCI preserved baseline renal vasomotor activity and allowed for recovery of dynamic autoregulatory responses over time.
Conclusions:
- SCI level and chronicity are critical determinants of renal microvascular regulation.
- High-thoracic SCI leads to persistent autonomic-vascular uncoupling and a loss of dynamic renal autoregulation.
- Disruption of dynamic renal autoregulation following high-thoracic SCI is a key mechanism of secondary kidney vulnerability after neurotrauma.
Keywords:
Spinal cord injuryblood pressure variabilitymyogenic mechanismrenal autoregulationrenal hemodynamicssympathetic nerve activityMore Related Videos
07:59A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts
Published on: October 7, 2014
09:22In Vivo Telemetry to Record Long-Term Cardiovascular Parameters, Temperature, and Activity in Spinal Cord Injury Rat Models
Published on: January 2, 2026
Related Concept Videos
01:18Disorders of the Autonomic Nervous System
The autonomic nervous system (ANS) is an intricate network of nerves that controls functions such as the regulation of heart rate, digestion, and blood pressure regulation. When this system malfunctions, it can lead to various disorders that affect multiple bodily functions. One common feature of many autonomic disorders is the involvement of smooth blood vessels, which play a crucial role in regulating blood flow throughout the body.
Raynaud's disease, also known as Raynaud's phenomenon, is a...
Raynaud's disease, also known as Raynaud's phenomenon, is a...
01:25Secondary Spinal Cord Injury llI: Pathophysiology
Early Ischemia and Ionic ImbalanceWithin minutes of spinal cord injury, a secondary cascade begins, progressing over hours to weeks. Vascular damage reduces blood flow, causing ischemia and mitochondrial dysfunction. ATP depletion leads to ion pump failure, membrane depolarization, sodium influx, potassium efflux, and water accumulation, resulting in cellular swelling. Increased intracellular calcium further disrupts mitochondria and accelerates cellular injury.Excitotoxicity and Neuronal...
01:18Neural Regulation of Blood Pressure
The neural regulation of blood pressure involves intricate interactions between the autonomic nervous system (ANS) and cardiovascular system, ensuring adequate perfusion of tissues. This regulation primarily occurs through baroreceptor and chemoreceptor reflexes, involving both short-term and long-term mechanisms.
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...
Baroreceptor Reflex
Baroreceptors, located in the carotid sinuses and aortic arch, detect changes in blood pressure. When blood pressure rises, these stretch-sensitive receptors...
01:14Spinal Cord Injury ll: Pathophysiology
Spinal cord injury progresses through two interconnected phases: primary injury and secondary injury.Primary InjuryPrimary injury happens at the moment of trauma and involves immediate mechanical damage to the spinal cord.Compression happens when broken vertebrae, herniated discs, or accumulating blood (such as a hematoma) press directly against the spinal cord, distorting its normal shape and function. In cases of contusion, the cord is bruised by a blunt force (like penetrating injuries or...
01:21Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
Clinical manifestationsPeripheral Arterial Disease (PAD) manifests through a range of symptoms, from the characteristic intermittent claudication to atypical presentations and severe complications in advanced stages. Intermittent claudication, a hallmark symptom of PAD, presents as exercise-induced muscle pain that typically resolves within minutes of rest. This pain is reproducible and stems from inadequate blood flow, leading to the accumulation of lactic acid produced during anaerobic...
01:18Blood and Nerve Supply to the Kidney
The kidneys are vital organs responsible for filtering and cleaning blood, removing waste products, and regulating electrolyte levels. To perform these essential functions, they require a constant and robust blood supply.
Bloody Supply to the Kidneys:
The kidneys receive their blood supply from the renal arteries, which branch off from the abdominal aorta—the main artery supplying the abdomen and lower body. The renal arteries enter the kidneys at the hilum, a notch on the medial side of each...
Bloody Supply to the Kidneys:
The kidneys receive their blood supply from the renal arteries, which branch off from the abdominal aorta—the main artery supplying the abdomen and lower body. The renal arteries enter the kidneys at the hilum, a notch on the medial side of each...