# The inhibitory effect of intraspinal microstimulation of the sacral spinal cord on nonlinear bladder reflex dynamics in cats

## TL;DR

This study explores using electrical stimulation in the sacral spinal cord of cats to control bladder reflexes, offering a new treatment for urinary incontinence and overactive bladder.

## Contribution

The study introduces sacral intraspinal microstimulation (ISMS) as a novel method to inhibit chaotic bladder reflexes.

## Key findings

- ISMS targeting the S2 spinal segment suppressed high-amplitude bladder contractions in cats.
- Bladder reflexes showed transitions between regular and chaotic dynamics, which ISMS could stabilize.
- The results suggest ISMS could be a promising alternative for managing overactive bladder.

## Abstract

Electrical stimulation of the pudendal nerve, pelvic nerve, sacral dorsal root ganglion (DRG), and spinal cord has been explored to treat urinary incontinence and overactive bladder (OAB). This study introduces sacral intraspinal microstimulation (ISMS) as a novel method to inhibit spontaneous bladder reflexes in anesthetized cats. In addition, we investigated the effects of intermittent and switching stimulation patterns on bladder inhibition.

The electrode was implanted in the dorsal horn of the S2 spinal cord. Bladder pressure was recorded under isovolumetric conditions, and the stimulation parameters were adjusted to inhibit spontaneous bladder contractions. Nonlinear dynamic methods, including chaos theory, were employed to analyze the complexity of bladder reflexes.

Results demonstrated that ISMS targeting the dorsal horn of the S2 spinal segment effectively suppressed high-amplitude spontaneous contractions. Furthermore, bladder reflexes exhibited complex dynamics, ranging from regular to chaotic patterns, with transitions between these states. Importantly, ISMS was able to stabilize these chaotic dynamics, leading to more controlled bladder behavior.

These findings suggest that sacral ISMS offers a promising, targeted alternative to traditional stimulation therapies, potentially providing a new therapeutic approach for managing OAB and urinary incontinence by regulating chaotic bladder activity.