Differential loss of spinal sensory but not motor neurons in the p75(NTR) knockout mouse

Abstract

Sensory neurons in the dorsal root ganglia (DRG) and motor neurons in the spinal cord express the 75 kDa low-affinity neurotrophin receptor (p75(NTR)) during prenatal development. The p75(NTR) gene knockout mouse provides a unique opportunity to assess the role of p75(NTR) during this period. Quantitative analysis of the p75(NTR) knockout mouse revealed a significant developmental loss of sensory neurons. In the cervico-thoracic ganglia approximately 75% of the neurons are lost, while in the lumbar ganglia the loss is approximately 50%. In contrast, motor neurons were not lost in either the cervical or lumbar spinal cord. These data suggest that p75(NTR) is essential for the prenatal surviva..