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Updated: Aug 21, 2026

Assessment of Morphine-induced Hyperalgesia and Analgesic Tolerance in Mice Using Thermal and Mechanical Nociceptive Modalities
Published on: July 29, 2014
[Nonspecific effect of morphine on the erythrocyte membrane]
Abstract:
The effect of low morphine concentrations on the plasmatic membranes of erythrocytes without opiate receptors was investigated. It was shown that the ATPase activity and hemolytic stability of erythrocytes, which characterize the state of cell membranes and the mobility of the near-membrane water phase, depend on the concentration of morphine, and this dependence is wave-like. The nonmonotonous dependence of the biological response was suggested to be due to changes in the structure of water hydrogen links near the membrane surface, induced by opiate molecules. The hypothesis was confirmed by the results of studies of morphine water solutions using the methods of fluorescent probe and light scattering. It was found that the intensity of light scattering by water and the mobility of its molecules considerably increase in the presence of strictly specified concentrations of morphine.
Insights
Low morphine concentrations affect erythrocyte membranes and water structure. This wave-like effect, observed in ATPase activity and hemolytic stability, is linked to morphine
Area of Science:
- Biochemistry
- Cell Biology
- Physical Chemistry
Context:
- Erythrocytes (red blood cells) lack opiate receptors, making them a model for studying direct membrane effects.
- Understanding how molecules interact with cell membranes is crucial for pharmacology and toxicology.
- The role of water structure in biological processes is an emerging area of research.
Purpose:
- To investigate the impact of low morphine concentrations on erythrocyte plasmatic membranes.
- To explore the relationship between morphine concentration and erythrocyte membrane properties (ATPase activity, hemolytic stability).
- To elucidate the mechanism behind the observed non-monotonous biological response, hypothesizing a role for altered water structure.
Summary:
- Morphine's effect on erythrocyte ATPase activity and hemolytic stability exhibits a wave-like, non-monotonous concentration dependence.
- This dependence suggests morphine alters the hydrogen bonding structure of water near the erythrocyte membrane surface.
- Studies using fluorescent probes and light scattering confirmed that specific morphine concentrations increase water light scattering and molecular mobility.
Impact:
- Reveals a novel, concentration-dependent interaction of morphine with cell membranes, independent of specific receptors.
- Highlights the significant influence of altered water structure on biological membrane functions.
- Provides a foundation for further research into water-mediated effects of small molecules on biological systems.
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