Gonadectomy-induced transcriptome changes in the ventral cervical spinal cord of male and female rats

Circulating sex steroids are critical for the development of neuroplasticity in the respiratory motor system. A primary locus of inducible respiratory neuroplasticity is the phrenic motor nucleus, a column of motor neurons in the ventral cervical spinal cord (C3-C5). In specific, exposure to acute intermittent hypoxia (AIH) induces strengthened synaptic connections to phrenic motor neurons and increased motor output; a form of neuroplasticity called phrenic long-term facilitation (pLTF). Gonadectomy (surgical removal of the testes in males and ovaries in females) reduces circulating sex steroids and eliminates AIH-induced phrenic pLTF in both females and males, implicating sex steroids as critical mediators for the development of neuroplasticity. To begin interrogating mechanisms of sex steroid influence on phrenic motor neurons and to determine the effect of gonadectomy on local gene expression, we performed RNA sequencing on ventral cervical spinal cord samples containing the phrenic motor nucleus. Our findings identified sex-specific gene expression in gonadally-intact rats and suggested that gonadectomy caused greater changes to the transcriptomes of male rats compared to females. Comparative gene expression profiling analysis of RNA-seq data for ventral cervical spinal cord tissue (C3-C6) of female and male rats with and without gonadectomy.