Detrusor urinae muscle

The detrusor urinae muscle is a smooth muscle^[1] of the urinary bladder wall. When urinating, it contracts to squeeze out urine. Otherwise, it remains relaxed to allow the bladder to fill. ^[2]

Additional recommended knowledge

How to quickly check pipettes?

Weighing the right way

Daily Visual Balance Check

Structure

The detrusor urinae muscle arises from the posterior surface of the body of the pubis in both sexes (musculi pubovesicales), and in the male from the adjacent part of the prostate and its capsule. They pass, in a more or less longitudinal manner, up the inferior surface of the bladder, over its vertex, and then descend along its fundus to become attached to the prostate in the male, and to the front of the vagina in the female. At the sides of the bladder the fibers are arranged obliquely and intersect one another.

References

1. ^ Response of guinea pig smooth and striated urethral sphincter to ...
2. ^ Netdoctor.co.uk - The bladder and how it works Reviewed by Dr Hilary McPherson, consultant obstetrician and gynaecologist and Dr Kate Patrick, specialist registrar