Fiber type-specific afferent nerve activity induced by transient contractions of rat bladder smooth muscle in pathological states

• Published in: PloS one Vol. 12; no. 12; p. e0189941
• Main Authors: Kuga, Nahoko, Tanioka, Asao, Hagihara, Koichiro, Kawai, Tomoyuki
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 21.12.2017; Public Library of Science (PLoS)
• Subjects: Afferent Pathways - drug effects; Analysis; Animal models; Animal research models; Animals; Biology and Life Sciences; Bladder; Body temperature; Catheters; Contraction; Cyclophosphamide; Cyclophosphamide - pharmacology; Female; Fibers; Inflammation; Laboratory animals; Medicine and Health Sciences; Muscle contraction; Muscle Contraction - drug effects; Muscle, Smooth - drug effects; Muscle, Smooth - pathology; Muscles; Nerves; Neurosciences; Pharmaceutical industry; Pharmacology; Physiological aspects; Physiology; Pressure; Prostaglandin E2; Rats; Rats, Sprague-Dawley; Research and Analysis Methods; Respiration; Rodents; Sensory neurons; Sensory receptors; Smooth muscle; Urinary bladder; Urinary Bladder - drug effects; Urinary Bladder - pathology; Urology; Japan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0189941

Bladder smooth muscle shows spontaneous phasic contractions, which undergo a variety of abnormal changes depending on pathological conditions. How abnormal contractions affect the activity of bladder afferent nerves remains to be fully tested. In this study, we examined the relationship between transient increases in bladder pressure, representing transient contraction of bladder smooth muscle, and spiking patterns of bladder afferent fibers of the L6 dorsal root, in rat pathological models. All recordings were performed at a bladder pressure of approximately 10 cmH2O by maintaining the degree of bladder filling. In the cyclophosphamide-induced model, both Aδ and C fibers showed increased sensitivity to transient bladder pressure increases. In the prostaglandin E2-induced model, Aδ fibers, but not C fibers, specifically showed overexcitation that was time-locked with transient bladder pressure increases. These fiber type-specific changes in nerve spike patterns may underlie the symptoms of urinary bladder diseases.