A15 Earthworm Smooth Muscle

This BSL PRO lesson describes the hardware and software setup necessary to record smooth muscle from earthworm gut, in vitro.

Experimental Objectives

1. To record the smooth muscle from an isolated segment of earthworm gut.
2. To measure the response of the smooth muscle during the administration of different drugs.
3. Observe the effect of temperature changes on the contractility of the smooth muscle.
4. * Plot log-dose response curves for 5HT or EPI, ACH and ACH in ATRO.

* This objective is covered in the introductory text and recording template for BSL 4 or above only.

Tasks Performed by the Student

• Test the effects of change in temperature:
  • Adjust the tension adjuster so that there is a small amount of force being applied to the gut.
  • Record baseline and temperature
  • Bathe the earthworm in cold Earthworm Ringer and record temperature d Earthworm Ringer.
  • Bathe the earthworm with warm Earthworm Ringer and record the temperature.
  • Bathe the earthworm with room temperature Earthworm Ringer and record the temperature.
• Test the effects of norepinephrine and acetylcholine:
  • Add saline with norepinephrine to the bath.
  • Drain and refill the bath with fresh Earthworm Ringer.
  • Add saline with acetylcholine to the bath.
• Test the effects of chemical depolarization:
  • Add saline containing KCl to the bath.
  • Replace the KCl with regular Earthworm Ringer.
  • Replace the regular earthworm saline with calcium-free earthworm saline.
  • Add saline with KCl solution and observe the response.
  • Replace the bath with regular earthworm saline and allow the rhythmicity and contraction amplitude to return to normal.

Student Prep & Distance Learning

Click the link(s) below for sample data and/or lesson procedure video(s), BSL PRO Lesson procedures (PDF) for human lessons*, and graph template files (*.gtl) for BSL PRO Lessons. If more than one .gtl is available, download the .gtl with the _suffix to match BSL version and hardware.

• Graph template for Lesson A15 with BSL PRO 4 or above
• Graph template for Lesson A15 with BSL PRO 3.6.6-3.7.7
• Click here to request the lesson procedure PDF - animal lessons are available by request only

Lesson Hardware

This lesson requires a Biopac Student Lab (BSL) System and the following hardware. If your BSL System does not include all hardware items, expand your system by selecting required items below. For more details, review the Lesson: L# BSL Lessons - see the Lab Manual or launch BSL; A# and H# BSL PRO Lessons, click the PDF link above to review full setup, recording, and analysis procedures.