title: Caffeine enhances micturition through neuronal activation in micturition centers.
abstract: Caffeine may promote incontinence through its diuretic effect, particularly in individuals with underlying detrusor overactivity, in addition to increasing muscle contraction of the bladder smooth muscle. Caffeine may also affect bladder function via central micturition centers, including the medial preoptic area, ventrolateral periaqueductal gray, and pontine micturition center. However, the biochemical mechanisms of caffeine in central micturition centers affecting bladder function remain unclear. In the present study, the effects of caffeine on the central micturition reflex were investigated by measuring the degree of neuronal activation, and by quantifying nerve growth factor (NGF) expression in rats. Following caffeine administration for 14 days, a urodynamic study was performed to assess the changes to bladder function. Subsequently, immunohistochemical staining to identify the expression of c‑Fos and NGF in the central micturition areas was performed. Ingestion of caffeine increased bladder smooth muscle contraction pressure and time as determined by cystometry. Expression levels of c‑Fos and NGF in all central micturition areas were significantly increased following the administration of caffeine. The effects on contraction pressure and time were the most potent and expression levels of c‑Fos and NGF were greatest at the lowest dose of caffeine. These results suggest that caffeine facilitates bladder instability through enhancing neuronal activation in the central micturition areas.
authors.affiliation: Department of Urology, Kangbuk Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 110‑746, Republic of Korea.
authors.forename: Young-Sam
authors.initials: YS
authors.lastname: Cho
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130‑701, Republic of Korea.
authors.forename: Il-Gyu
authors.initials: IG
authors.lastname: Ko
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130‑701, Republic of Korea.
authors.forename: Sung-Eun
authors.initials: SE
authors.lastname: Kim
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130‑701, Republic of Korea.
authors.forename: Lakkyong
authors.initials: L
authors.lastname: Hwan
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130‑701, Republic of Korea.
authors.forename: Mal-Soon
authors.initials: MS
authors.lastname: Shin
authors.affiliation: Department of Physiology, College of Medicine, Kyung Hee University, Seoul 130‑701, Republic of Korea.
authors.forename: Chang-Ju
authors.initials: CJ
authors.lastname: Kim
authors.affiliation: Department of Physical Education, Graduate School of Education, Sangmyung University, Seoul 110‑743, Republic of Korea.
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Department of Physical Activity Design, College of Science, Hanseo University, Seosan 356‑706, Republic of Korea.
authors.forename: Jun-Jang
authors.initials: JJ
authors.lastname: Jin
authors.affiliation: Department of Anesthesiology and Pain Medicine, Gangdong Kyung Hee Hospital, College of Medicine, Kyung Hee University, Seoul 134‑727, Republic of Korea.
authors.forename: Jun-Young
authors.initials: JY
authors.lastname: Chung
authors.affiliation: Department of Urology, Gachon University Gil Medical Center, Incheon 405‑760, Republic of Korea.
authors.forename: Khae-Hawn
authors.initials: KH
authors.lastname: Kim
mesh_terms: D000818:Animals; D002110:Caffeine / Q000494:pharmacology*; D005260:Female; D009119:Muscle Contraction / Q000187:drug effects / Q000235:genetics; D009130:Muscle, Smooth / Q000187:drug effects; D020932:Nerve Growth Factor / Q000235:genetics; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D001743:Urinary Bladder / Q000187:drug effects*; D014554:Urination / Q000187:drug effects* / Q000235:genetics; D014563:Urodynamics / Q000187:drug effects* / Q000235:genetics
chemical_list: D016760:Proto-Oncogene Proteins c-fos; D002110:Caffeine; D020932:Nerve Growth Factor