Related Experiment Video

Updated: Sep 19, 2025

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing

Ultrasonography of the Adult Male Urinary Tract for Urinary Functional Testing

Published on: August 14, 2019

Voiding symptom severity varies independently from non-adrenergic prostate smooth muscle contractions in patients

Patrick Keller¹, Sheng Hu¹, Philip Nicola¹

¹Department of Urology, LMU University Hospital, LMU Munich, Munich, Germany.

Frontiers in Physiology

|June 16, 2025

Abstract

Background:

Resistance of voiding symptoms to α₁-blockers in benign prostatic hyperplasia (BPH) has been provisionally explained by non-adrenergic prostate smooth muscle contraction. Here, we examined relationships between contractions and voiding symptoms in prostate tissues from laser-enucleation.

Methods:

Tissues were obtained from holmium and thulium laser enucleation. Contractions were induced by endothelin-1, U46619, noradrenaline and electric field stimulation (EFS). E_max values were analyzed for correlation with international prostate symptom score (IPSS), and compared to tissues from patients without surgery for BPH.

Results:

Noradrenaline- and EFS-induced contractions were higher with severe (IPSS 20-35) than moderate symptoms (IPSS 8-19) (E_max noradrenaline 66% vs 113% of KCl-induced contractions; EFS 33% vs 66%). Endothelin-1- and U46619-induced contractions were already maximum with moderate symptoms (endothelin-1 117% moderate, 135% severe; U46619 23%, 27%). Within 8-21 points, IPSS increased with E_max values for noradrenaline and EFS (r = 0.545, r = 0.448), but not with endothelin-1- or U46619-induced contractions. Endothelin-1-induced contractions were similar to noradrenaline-induced contractions (E_max endothelin-1 126% of KCl, noradrenaline 96%), and exceeded EFS- (52%) and U46619-induced contractions (25%). E_max values for endothelin-1 were similar between laser-enucleated patients and patients without surgery for BPH (127%), while E_max values for U46619 were higher in tissues from patients without surgery for BPH (59%) compared to laser-enucleated tissues.

Conclusion:

Symptom severity increases with α₁-adrenergic, but not with non-adrenergic contractions in patients undergoing surgery for BPH. Endothelin-1-induced contractions are similar to noradrenaline-induced contractions. Conditions necessitating BPH surgery may not necessarily depend on α₁-adrenergic tone, but may involve non-adrenergic contractions or factors beyond contraction.

Keywords:

benign prostatic hyperplasia (BPH)holmium laser enucleation of the prostate (HoLEP)human tissue international prostate symptom score (IPSS)lower urinary tract symptoms (LUTS)smooth muscle contraction voiding symptoms

More Related Videos

Photoselective Vaporesection of the Prostate via an End-firing Lithium Triborate Crystal Laser

Photoselective Vaporesection of the Prostate via an End-firing Lithium Triborate Crystal Laser

Published on: May 9, 2018

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

Published on: August 18, 2014

Related Concept Videos

Urodynamic Studies: Uroflowmetry

Urodynamic Studies: Uroflowmetry

Uroflowmetry is a non-invasive urodynamic test designed to measure various aspects of urination, including volume, flow rate, and the time to void. This test is crucial for diagnosing and assessing conditions such as bladder outlet obstruction, bladder dysfunction, incomplete bladder emptying, incontinence, and urinary tract blockages caused by benign prostatic hyperplasia (BPH) and urethral strictures.Pre-Test Instructions:Before a uroflowmetry test, patients are typically advised to drink...

The Micturition Reflex

The Micturition Reflex

Urination, or micturition involves the coordination of the bladder's detrusor muscle and two sphincters to ensure controlled bladder emptying.
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating...

Adrenergic Antagonists: Pharmacological Actions of ɑ-Receptor Blockers

Adrenergic Antagonists: Pharmacological Actions of ɑ-Receptor Blockers

α-Adrenergic antagonists, known as α-blockers, exert their effects by inhibiting α-adrenoceptors, leading to specific physiological actions. α1-blockers and α2-blockers have distinct pharmacological actions and therapeutic applications.
α1-blockers: These drugs inhibit α1-adrenoceptors on smooth muscle cells, resulting in vasodilation. This vasodilation lowers blood pressure, making α1-blockers valuable in treating hypertension. Additionally,...

Urinary Tract Calculi VI: Surgical Management

Urinary Tract Calculi VI: Surgical Management

Procedures for Kidney StonesMedical intervention is necessary when kidney stones or renal calculi are too large to pass spontaneously (typically greater than 5 millimeters) when stones are accompanied by symptomatic infection (such as fever or pyelonephritis), when they impair kidney function, or when they cause persistent symptoms like severe pain, nausea, or urinary retention. Additionally, patients with only one kidney or those who cannot be treated with medical management also require...

Urinary Bladder

Urinary Bladder

The urinary bladder is a hollow, muscular sac that temporarily stores urine before it is expelled from the body. It can hold approximately 600 mL of urine prior to micturition. The bladder is retroperitoneal and located behind the pubic symphysis in the pelvic floor.
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...

Anatomy of the Genitourinary System II: Bladder and Urethra

Anatomy of the Genitourinary System II: Bladder and Urethra

The lower urinary system consists of the urinary bladder and urethra, which are essential in storing and expelling urine from the body. Together with the internal and external sphincters, these structures work together to regulate urination effectively.Anatomy of the BladderThe urinary bladder is a muscular, stretchable organ behind the pubic bone and in front of the rectum. In females, the bladder is positioned anterior to the vagina and inferior to the uterus, while in males, it is located...

Articles linked to this work by shared authors, journal, and citation graph.

PSA density for clinically significant prostate cancer detection: a retrospective cohort study on the influence of age and prostate volume.

World journal of urology·2026

miR-143-3p integrates contractility and growth in benign prostate stromal cells.

Cellular signalling·2026

Transition Zone PSA Density Does Not Improve Detection of Clinically Significant Prostate Cancer over Whole-Gland PSA Density: A Volume-Stratified Analysis in 3,958 Patients.

Urologia internationalis·2026

Unraveling the Knot: The Impact of Distal vs. Proximal Implantation Technique on Adjustable Transobturator Male Sling (ATOMS) Outcomes for the Treatment of Stress Urinary Incontinence.

Neurourology and urodynamics·2026

A Bioactive Benzyl Terpene from Acridocarpus smeathmannii Inhibits Human Prostate Smooth Muscle Contractility.

Molecules (Basel, Switzerland)·2026

Switching lasers: assessing the learning curves of surgeons with different levels of surgical experience when switching from HoLEP to pulsed Thulium YAG lasers for ThuLEP.

Frontiers in surgery·2026

See all related articles