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Updated: Mar 29, 2026
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Application of Chronic Stimulation to Study Contractile Activity-induced Rat Skeletal Muscle Phenotypic Adaptations
Published on: January 25, 2018
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ATP-induced changes in rat skeletal muscle contractility.
A I Gabdrakhmanov1, A E Khayrullin2, C H Grishin2,3
1Kazan Federal (Volga Region) University, Kazan, Russia.
The International Journal of Risk & Safety in Medicine
|December 8, 2015
Summary
Norepinephrine lessens the inhibitory effect of adenosine triphosphate (ATP) on skeletal muscle contraction. This suggests an adaptive stress response where ATP
Area of Science:
- Neuroscience and Pharmacology
- Skeletal Muscle Physiology
Background:
- Extracellular purines like adenosine triphosphate (ATP) and adenosine regulate cell functions via P2 and P1 receptors.
- ATP is metabolized to adenosine, acting as a functional antagonist and influencing neuromuscular junctions.
- Receptors for ATP and adenosine are widespread, making them significant physiological targets.
Purpose of the Study:
- Investigate the effects of ATP and adenosine on rat skeletal muscle contraction.
- Assess the impact of catecholamines, specifically norepinephrine, on these purinergic effects.
Main Methods:
- Isometric contractions of rat soleus muscles were recorded.
- Muscle contraction amplitude and time characteristics were analyzed.
- Standard Krebs solution with added agents (ATP, adenosine, norepinephrine) was used.
Main Results:
- Norepinephrine increased contraction time in both fast and slow skeletal muscles.
- Adenosine's inhibitory effect on contraction force was maintained in the presence of norepinephrine.
- ATP's inhibitory effect on contraction force was reduced by half with norepinephrine.
Conclusions:
- Norepinephrine modulates purinergic signaling in skeletal muscle.
- The reduced inhibitory effect of ATP by norepinephrine may be an adaptive response to acute stress.
- These findings highlight the complex interplay between catecholamines and purines in muscle function.
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