BDNF but not NT-4 is required for normal flexion reflex plasticity and function

Neurotrophins like BDNF can change how signals are passed between nerve cells in the brain and spinal cord. This study looks at how BDNF and NT-4 affect reflexes, especially those related to pain, using mice that lack either BDNF or NT-4. The researchers found that mice without BDNF had weaker responses to painful stimuli and reduced wind-up, a process where repeated stimulation causes increasing pain. However, mice without NT-4 had normal pain responses. This suggests that BDNF, but not NT-4, plays a crucial role in how the spinal cord processes pain signals. The findings indicate that BDNF released from sensory neurons directly affects pain transmission in the spinal cord.

• 1
  BDNF-deficient mice showed reduced ventral root potential (VRP) evoked by stimulating nociceptive primary afferents, indicating impaired nociceptive transmission.
• 2
  Activity-dependent plasticity of the VRP (wind-up) was substantially reduced in BDNF-deficient mice, suggesting BDNF's role in spinal cord sensitization.
• 3
  NT-4 null mutant mice displayed normal reflex properties, indicating that NT-4 is not essential for basal nociceptive transmission or reflex plasticity.