Aims: Dorsal root ganglia contain heterogeneous populations of primary afferent neurons that transmit various sensory stimuli. This functional diversity may be correlated with differential expression of voltage-gated K(+) (Kv) channels. Here, we examine cellular distributions of Kv4 pore-forming and ancillary subunits that are responsible for fast-inactivating A-type K(+) current.
View Article and Find Full Text PDFLow Urin Tract Symptoms
September 2009
Hyperexcitability of C-fiber bladder afferent pathways has been proposed to contribute to urinary frequency and bladder pain in chronic bladder inflammation including interstitial cystitis. However, the detailed mechanisms inducing afferent hyperexcitability after bladder inflammation are not fully understood. Thus, we investigated changes in the properties of bladder afferent neurons in rats with bladder inflammation induced by intravesical application of hydrochloric acid.
View Article and Find Full Text PDFPurpose: Although cannabinoid receptor expression has been demonstrated in human brain and other peripheral neuronal tissues, definitive expression of these receptors in the human bladder has not been reported. Consequently we investigated the expression of functional cannabinoid 1 and 2 receptors in human bladder detrusor and urothelium.
Materials And Methods: Human bladders were micro-dissected for detrusor (6) and urothelium (8), and analyzed for cannabinoid 1 and 2 mRNA expression using real-time quantitative polymerase chain reaction, and for protein expression using immunohistochemistry and Western blot.
Afferent pathways innervating the urinary bladder consist of myelinated Adelta- and unmyelinated C-fibers, the neuronal cell bodies of which correspond to medium and small-sized cell populations of dorsal root ganglion (DRG) neurons, respectively. Since hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channel currents have been identified in various peripheral sensory neurons, we examined the expression of isoforms of HCN channels in the L6-S1 spinal cord and bladder afferent neurons from L6-S1 DRG in rats. Among HCN-1, HCN-2 and HCN-4 channel subtypes, positive staining with HCN-2 antibodies was found in the superficial dorsal horn of the spinal cord and small- and medium-sized unidentified DRG neurons.
View Article and Find Full Text PDFWe investigated whether primary afferent neurons innervating different regions of the lower urinary tract have different histochemical and electrophysiological properties. Neurons in rat L6-S1 DRG were identified by axonal transport of a fluorescent dye. Neurofilament-negative C-fiber cells comprise approximately 70% of bladder and proximal urethral afferent neurons that send axons through the pelvic nerves, but comprise a smaller proportion (51%) of distal urethral neurons that send axons through the pudendal nerves.
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