Physiology of Human Body Systems
Activity of Gastrointestinal
Smooth Muscle Worksheet
Due by:
2 pm 30th March and 1st April
Pre-practical Reading: Vander, 12th Edition:
Section 6D.4 (pp 175-180), Section 15.2 (pp 521-522), Section 15.4 (pp 528-529, 536-538 & 542-543).
Name: ________________________________
Student ID: _____________________________
Marks: ________/100______________________
Introduction
Give a brief description in your own words of the objectives and aims of this practical. (5)
A. Responses to Nerve Stimulation
Attach a copy of your experimental recordings showing a period of spontaneous contractions and the response to stimulating the nerves at 20 Hz with both a voltage that produced only a modest response and the voltage that produced the maximal response. (5)
1) Briefly describe the response of the ileum when it is unstimulated and during stimulation of the nerves. (5)
2) What is the frequency of the regular spontaneous contractions of the ileum? What causes these spontaneous contractions? (5)
Attach a copy of your experimental recordings showing the response to stimulating the nerves with the maximal voltage at both 5 Hz and 50 Hz. (5)
3) Explain the effect of altering stimulus frequency on the response of the ileum to nerve stimulation. (5)
B. Mimicking the Action of the Autonomic Nervous System using Drugs
Attach copies of your experimental recordings showing the response of the ileum to the direct addition of noradrenaline and of acetylcholine to the tissue bath. (10)
1) What was the final bath concentration of noradrenaline you used? Briefly describe the response of the ileum to the direct addition of noradrenaline. (5)
2) What was the final bath concentration of acetylcholine you used? Briefly describe the response of the ileum to the direct addition of acetylcholine. (5)
3) Since an inhibitory response to nerve stimulation was observed in all (or most) of