Related Experiment Video
Updated: May 10, 2026
10:26
Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Human colonic smooth muscle: electrical and contractile activity in vitro
Gut
|March 1, 1986
Summary
Human colonic smooth muscle exhibits distinct electrical and contractile activities. The sigmoid colon shows the most powerful contractions, with frequency influenced by muscle orientation and location.
Area of Science:
- Gastroenterology
- Physiology
- Smooth Muscle Biology
Background:
- Understanding the electrical and contractile properties of human colonic smooth muscle is crucial for comprehending gastrointestinal motility.
- Previous studies have investigated smooth muscle activity, but detailed in vitro analysis of human colonic tissues from different regions is limited.
Purpose of the Study:
- To characterize the extracellular electrical and contractile activities of human colonic smooth muscle in vitro.
- To compare these activities between different regions of the colon and muscle orientations.
- To investigate the effect of mechanical stretching on contractile frequency.
Main Methods:
- In vitro recording of extracellular electrical and contractile activities from human colonic smooth muscle strips (taenia, intertaenial, circular orientations).
- Analysis of oscillation frequencies and superimposed spikes.
- Assessment of contractile force and frequency based on colonic origin (sigmoid, right, left).
- Application of mechanical stretch to observe effects on contractile frequency.
Main Results:
- Serosal electrical activity showed continuous oscillations at approximately 28/min.
- Submucosal electrical activity in circularly oriented strips had lower oscillation frequencies (24/min) compared to serosal recordings.
- Contractile force was greatest in sigmoid colon strips.
- Contractile frequency varied significantly by colonic region and orientation, with right colon circular strips (6.3/min) exhibiting higher frequency than left colon strips (3.4/min).
- Stretching increased contractile frequency to match electrical oscillation frequency.
Conclusions:
- Human colonic smooth muscle exhibits region- and orientation-dependent electrical and contractile properties.
- The sigmoid colon is a primary site of powerful contractile activity.
- Mechanical stretch plays a role in regulating colonic smooth muscle contractile frequency, potentially synchronizing it with electrical activity.
Related Concept Videos
01:13Structure and Organization of Smooth Muscles
Smooth muscle tissue is a type of muscle tissue that can be found lining various vital organs in the human body, including the lungs, blood vessels, digestive tract, and respiratory tract. This type of tissue is responsible for regulating the movements of these organs, playing crucial roles in the functioning of various systems, including the vascular, digestive, respiratory, and urinary systems.
Structure of smooth muscle cell
Smooth muscle cells are spindle-shaped with tapering ends and a...
Structure of smooth muscle cell
Smooth muscle cells are spindle-shaped with tapering ends and a...
01:23Functions of Smooth Muscles
Smooth muscles are an important type of muscle tissue that plays a vital role in the involuntary movements of internal organs. For example, they help regulate the movement of food through the gut and the flow of blood through the circulatory system.
Function of visceral smooth muscles
Visceral smooth muscle is found in the walls of all hollow organs, except the heart, and is a key player in the involuntary movements that drive the functioning of these internal organs. This tissue is arranged in...
Function of visceral smooth muscles
Visceral smooth muscle is found in the walls of all hollow organs, except the heart, and is a key player in the involuntary movements that drive the functioning of these internal organs. This tissue is arranged in...
01:25Smooth Muscle Contraction
Smooth muscle contraction is a complex process vital for various bodily functions, from maintaining blood vessel tension to facilitating the movement of food through the digestive tract. Unlike striated muscles, smooth muscle contraction begins more slowly and lasts longer.
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
01:11Enteric Nervous System: Regulation of GI Motor Activity
The Enteric Nervous System (ENS) plays a pivotal role in regulating gastrointestinal or GI motor activity. This complex network of nerves, deeply embedded within the gut wall, responds to changes in the gut environment and receives input from both the autonomic nervous system and the central nervous system. By doing so, the ENS operates various programs tailored to the body's nutritional status and needs.
During periods of fasting, the ENS initiates the migrating myoelectric complex, a program...
During periods of fasting, the ENS initiates the migrating myoelectric complex, a program...
01:26Imaging Studies III: Gastrointestinal Motility Studies and Virtual Colonoscopy
This lesson explores three gastrointestinal imaging techniques: radionuclide testing, colonic transit studies, and virtual colonoscopy.
Radionuclide Testing
Radionuclide testing is a sophisticated medical technique for assessing gastrointestinal motility. It focuses on gastric emptying and colonic transit time. Radioactive markers track the movement of food through the digestive system, providing insights into gastrointestinal disorders.
In gastric emptying studies, a meal's liquid and solid...
Radionuclide Testing
Radionuclide testing is a sophisticated medical technique for assessing gastrointestinal motility. It focuses on gastric emptying and colonic transit time. Radioactive markers track the movement of food through the digestive system, providing insights into gastrointestinal disorders.
In gastric emptying studies, a meal's liquid and solid...