Expression of receptors for glial cell line-derived neurotrophic factor family ligands in sacral spinal cord reveals separate targets of pelvic afferent fibers

Abstract

Nerve growth factor has been proposed to mediate many structural and chemical changes in bladder sensory neurons after injury or inflammation. We have examined the expression of receptors for the glial cell line-derived neurotrophic factor (GDNF) family within sensory terminals located in the sacral spinal cord and in bladder-projecting sacral dorsal root ganglion neurons of adult female Sprague-Dawley rats. Nerve fibers immunolabelled for GFRα1 (GDNF receptor), GFRα2 (neurturin receptor), or GFRα3 (artemin receptor) showed distinct distribution patterns in the spinal cord, suggesting separate populations of sensory fibers with different functions: GFRα1-labeled fibers were in outer lamina I..