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Published on: November 27, 2014
Effect of morphine on Fc-mediated phagocytosis by murine macrophages in vitro
1Department of Psychiatry, Emory University School of Medicine, Atlanta, GA 30306, USA.
Abstract:
Acute exposure to morphine has been shown to inhibit phagocytosis in murine macrophages, whereas chronic exposure results in apparent desensitization. We now show that morphine may be either inhibitory or stimulatory depending on concentration and exposure time. Furthermore, under some conditions drug withdrawal from putatively desensitized cells will result in inhibition of phagocytosis, suggesting that a state akin to dependence has developed. Desensitization can also develop with intermittent exposures if the opiate-free period between drug exposures is shorter than 4 h. These effects of morphine on macrophages are important in understanding the role of this drug as an immunomodulatory agent.
Insights
Morphine
Area of Science:
- Immunology
- Pharmacology
Background:
- Morphine's acute exposure inhibits phagocytosis in murine macrophages.
- Chronic morphine exposure leads to apparent desensitization of macrophages.
Purpose of the Study:
- To investigate the concentration and time-dependent effects of morphine on macrophage phagocytosis.
- To explore the development of morphine dependence and desensitization in macrophages.
Main Methods:
- Murine macrophages were exposed to varying concentrations and durations of morphine.
- Phagocytic activity was measured under different drug exposure and withdrawal conditions.
Main Results:
- Morphine's effect on phagocytosis is concentration and time-dependent, acting as either an inhibitor or stimulator.
- Drug withdrawal from desensitized macrophages can inhibit phagocytosis, indicating dependence.
- Intermittent morphine exposure with <4h intervals leads to desensitization.
Conclusions:
- Morphine exhibits complex immunomodulatory effects on macrophage phagocytosis.
- Understanding these effects is crucial for evaluating morphine's role in immune function.
- Morphine can induce states of desensitization and dependence in macrophages.
