AB097. Conduction block of mammalian myelinated nerve by local cooling to 15–30 °C after a brief heating

Background: This study aimed at understanding thermal effects on nerve conduction and developing new methods to produce a reversible thermal block of axonal conduction in mammalian myelinated nerves. Methods: In 13 cats, conduction block of pudendal nerves by cooling (5–30 °C) or heating (42–54 °C) a small segment of the nerve was monitored by the urethral striated muscle contractions and increases in intraurethral pressure induced by intermittent electrical stimulation of the nerve. Results: Cold block was observed at 5–15 °C while heat block occurred at 50–54 °C. Cold block was fully reversible, but only brief complete heat block was reversible. A brief reversible complete heat block at 50–54 °C significantly increased the cold block temperature to 15–30 °C. Conclusions: This study discovered a novel method to block mammalian myelinated nerves at 15–30 °C, providing the possibility to develop an implantable device to block axonal conduction and treat many chronic diseases.