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PubMed · 16698002

Morphine modulates monocyte-macrophage conversion phase.

Ikuske Hatsukari·Naoko Hitosugi·Amit Dinda·Pravin C Singhal
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Abstract

Monocyte migration and their activation into the macrophage phenotype play a role in the modulation of tissue injury. We studied the effect of morphine on the monocyte-macrophage conversion phase (MMCP). Phorbol 12-myristate 13-acetate (PMA) activated THP-1 cells and promoted their adhesion to the substrate. Morphine inhibited PMA-induced MMCP. However, opiate receptor antagonists attenuated this effect of morphine. Interestingly, PMA as well as morphine-stimulated superoxide production by monocytes. Superoxide dismutase (SOD) not only inhibited PMA-mediated MMCP but also attenuated the inhibitory effect of morphine. PMA not only enhanced adhesion of monocytes to a filter but also promoted their migration. These findings suggest that the PMA-induced macrophage phenotype conversion may be accelerating their migration; whereas, morphine may be preventing the migration of monocytes by inhibiting MMCP.

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Cell AdhesionCell DifferentiationCell MovementCells, CulturedHumansMacrophagesMonocytesMorphineNarcotic AntagonistsReceptors, OpioidSuperoxidesTetradecanoylphorbol AcetateJournal ArticleResearch Support, N.I.H., Extramural

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Ikuske Hatsukari, Naoko Hitosugi, Amit Dinda, Pravin C Singhal. 2006-05-15. Morphine modulates monocyte-macrophage conversion phase.. https://doi.org/10.1016/j.cellimm.2006.03.004

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