PDA

View Full Version : defecation


IMG SURVIVOR
11-16-2006, 05:32 AM
Know you are in the ER and a patient ask you Doc I heard that before you defecate one of your sphinters are tight close and the other is relax and when you are defecating both sphinters are relax.

Which one is relax before defecation?
What type of tissue you will find in the one that you control?

Who know the fast and slow walk of diarrhea?:cool:

drdeb
11-17-2006, 02:55 AM
The smooth internal anal sphincter muscle maintains a tonic contraction during continence, due to its sympathetic fibres from the lumbar medulla

The muscle relaxes due to its parasympathetic, cholinergic fibres in the pelvic splancnic nerves (S2-S4).

The strong spinal reflex produces relaxation of the smooth muscles of the internal anal sphincter and contraction of the striated muscles of the external anal sphincter inhibiting the reflex and causing receptive relaxation just before defaecation.

what do u mean by fast and slow WALK? …I did not understand it :confused:
plz explain....