HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 295/3/E559    most recent 90289.2008v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Peng, H.-Y. Articles by Lin, T.-B. Search for Related Content PubMed PubMed Citation Articles by Peng, H.-Y. Articles by Lin, T.-B.

Estrous cycle variation of TRPV1-mediated cross-organ sensitization between uterus and NMDA-dependent pelvic-urethra reflex activity

¹Department of Veterinary Medicine, College of Veterinary Medicine, National Chung-Hsing University; ²Department of Physiology, College of Medicine, and ³Department of Obstetrics and Gynecology, Chung-Shan Medical University Hospital, Chung-Shan Medical University, Taichung; ⁴Department of Obstetrics and Gynecology, Chang-Gung Memorial Hospital, Taoyuan; ⁵School of Physical Therapy, College of Medicine, China Medical University; ⁶Division of Urology, Department of Surgery, Taichung Veterans General Hospital, Taichung; ⁷Department of Medicine, Saint Paul's Hospital, Taoyuan; and ⁸Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan

Submitted 13 March 2008 ; accepted in final form 19 June 2008

Cross-organ sensitization between the uterus and the lower urinary tract (LUT) underlies the high concurrence of pelvic pain syndrome and LUT dysfunctions, and yet the role of gonadal steroids is still unknown. We tested the hypothesis that cross-organ sensitization on pelvic-urethra reflex activity caused by uterine capsaicin instillation is estrous cycle dependent. When compared with the baseline reflex activity (1.00 ± 0.00 spikes/stimulation), uterine capsaicin instillation significantly increased reflex activity (45.42 ± 9.13 spikes/stimulation, P < 0.01, n = 7) that was corroborated by an increase in phosphorylated NMDA NR2B (P < 0.05, n = 4) but not NR2A subunit (P > 0.05, n = 4) expression. Both intrauterine pretreatment with capsazepine (5.02 ± 2.11 spikes/stimulation, P < 0.01, n = 7) and an intrathecal injection of AP5 (3.21 ± 0.83 spikes/stimulation, P < 0.01, n = 7) abolished the capsaicin-induced cross-organ sensitization and the increment in the phosphorylated NR2B level (P < 0.05, n = 4). The degrees of the cross-organ sensitization increased in a dose-dependent manner with the concentration of instilled capsaicin from 100 to 300 µM in both the proestrus and metestrus stages, whereas they weakened when the concentrations were higher than 1,000 µM. Moreover, the cross-organ sensitization caused by the uterine capsaicin instillation increased significantly in the rats during the proestrus stage when compared with the metestrus stage (P < 0.01, n = 7). These results suggest that estrogen levels might modulate the cross-organ sensitization between the uterus and the urethra and underlie the high concurrence of pelvic pain syndrome and LUT dysfunctions.

transient receptor potential vanilloid subfamily member 1; N-methyl-D-aspartate; pelvic pain syndrome; central sensitization; spinal reflex potentiation; capsaicin; spinal cord

This article has been cited by other articles:

				H.-Y. Peng, G.-D. Chen, K.-C. Tung, Y.-W. Chien, C.-Y. Lai, M.-C. Hsieh, C.-H. Chiu, C.-H. Lai, S.-D. Lee, and T.-B. Lin Estrogen-dependent facilitation on spinal reflex potentiation involves the Cdk5/ERK1/2/NR2B cascade in anesthetized rats Am J Physiol Endocrinol Metab, August 1, 2009; 297(2): E416 - E426. [Abstract] [Full Text] [PDF]

				S.-L. Chen, Y.-H. Huang, Y.-L. Kao, G.-D. Chen, C.-L. Cheng, H.-Y. Peng, J.-M. Liao, P.-C. Huang, S.-J. Tsai, and T.-B. Lin Acute anal stretch inhibits NMDA-dependent pelvic-urethra reflex potentiation via spinal GABAergic inhibition in anesthetized rats Am J Physiol Renal Physiol, October 1, 2008; 295(4): F923 - F931. [Abstract] [Full Text] [PDF]