尿道括约肌

尿道括约肌(英语:urethral sphincter)发源于坐耻支英语ischiopubic ramus,另一端探入互相交错的肌纤维之中。它由两块肌肉构成,由阴部神经位于深层会阴部分所控制,依照神经指示来收缩尿道[1]

尿道外括约肌包裹着尿道膜

尿道括约肌可分为两部分:尿道内括约肌英语internal sphincter muscle of urethra与尿道外括约肌。其中,尿道内括约肌位于膀胱内侧出口、尿道、膀胱接口处,是逼尿肌的延伸,由平滑肌构成,因此其运动即可为非自主也可自主。这是控制排尿的主要肌肉。

参考资料

  1. ^ Maclean, Allan; Reid, Wendy. 40. Shaw, Robert (编). Gynaecology. Edinburgh New York: Churchill Livingstone/Elsevier. 2011: 599–612. ISBN 978-0-7020-3120-5; Access provided by the University of Pittsburgh 

外部连接

  • Anatomy figure: 41:06-04 at Human Anatomy Online, SUNY Downstate Medical Center - "Muscles of the female urogenital diaphragm (deep perineal pouch) and structures located inferior to it."