Morphological and physiological characteristics of urethral circular and longitudinal smooth muscle
Related Experiment Video
Updated: Oct 7, 2026

An Optimized Method To Isolate Female Mouse Urethral Epithelium For Single-Cell And Immunofluorescence Analysis
Published on: June 12, 2026
A F Brading1, N Teramoto, N Dass
1Oxford Continence Group, University Department of Pharmacology, UK.
Abstract:
The urethral wall contains circular and longitudinal smooth muscle. Both layers can develop spontaneous tone, and contract further or relax in response to excitatory or inhibitory stimuli. In the pig the cells do not generate action potentials, and the membranes possess L-type calcium channels and a variety of potassium channels which may modulate the membrane potential and tone. The importance of these layers in generating the urethral pressure is not well understood in the human, but it seems likely that the circular smooth muscle is involved in generating urethral pressure in the pig.
Related Concept Videos
Urethra
The anatomy of the urethra differs between males and females. In females, the urethra is short, measuring about 3–4 cm in length, and opens anterior to the vaginal opening. In males, the urethra is longer and passes through the penis, serving dual purposes: expelling urine and ejaculating semen. The male urethra is...
Ureters
Structure and Organization of Smooth Muscles
Structure of smooth muscle cell
Smooth muscle cells are spindle-shaped with tapering ends and a...
Anatomy of the Genitourinary System II: Bladder and Urethra
Functions of Smooth Muscles
Function of visceral smooth muscles
Visceral smooth muscle is found in the walls of all hollow organs, except the heart, and is a key player in the involuntary movements that drive the functioning of these internal organs. This tissue is arranged in...
Fascicle Arrangement in Skeletal Muscles
The four primary types of muscle based on fascicle arrangement are:

