Underactive bladder in aging rats is associated with a reduced number of serotonin-expressing cells in the urethra and is improved by serotonin application to the urethra

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Coelho, A (Author) Other; Charrua A. (Author) FMUP; Oliveira, R (Author) Other; Cavaleiro, H (Author) Other; Cruz C.D. (Author) FMUP; Francisco Cruz (Author) FMUP

Journal

Title: LUTS: Lower Urinary Tract Symptoms

Vol. 11

Pages: 248-254

ISSN: 1757-5664

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 9 Citations

Other information

Authenticus ID: P-00Q-S5V

DOI: 10.1111/luts.12273

Abstract (EN): The aim of this study was to determine whether aging-related detrusor underactivity (DU) involves a decrease in 5-hydroxytryptamine (5-HT-positive)-expressing urethral cells and whether 5-HT stimulation of urethral sensory fibers improves detrusor function. Cystometries were performed in young (6 months) and aged (18-24 months) female Wistar rats. Aged rats with voiding contractions (VC) that were 2SD below the mean of those in young rats were considered to have DU. Bladder voiding efficiency (BVE) was calculated during saline or 5-HT solution cystometries. Rats were perfusion-fixed with a fixative solution (paraformaldehyde, PFA 4%) through the circulatory system and the urethra sectioned to count the number of 5-HT-immunoreactive (IR) cells. Isovolumetric cystometry was performed while irrigating the urethra with saline or 5 mu M-HT solution. Two-tailed unpaired t tests were used to determine the significance of differences. In aged DU rats, the mean (+/- SD) VC frequency was 0.24 +/- 0.07 per minute, with an amplitude of 15 +/- 3 cm H2O. The mean (+/- SD) number of 5-HT-IR cells in the urethra of aged DU and young rats was 90 +/- 11 and 182 +/- 25, respectively (P < 0.01). 5-HT improved the mean (+/- SD) BVE of aged DU rats from 49 +/- 3% to 78 +/- 2% (P < 0.001). In isovolumetric cystometries, detrusor pressure during irrigation of the urethra with saline was 18 +/- 1 cm H2O, compared with 39 +/- 2 cm H2O during irrigation with 5-HT solution (P < 0.05). In rats, DU associated with aging is accompanied by a decrease in the number of 5-HT-positive cells. The results suggest that decreased 5-HT availability decreases urethral sensory fiber excitation, leading to a decrease the number of effective VC.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 7