Morphine neutrophils

Although controversial, findings as to how chronically administered morphine modulates neutrophil chemotaxis and function, a growing consensus believes that morphine is suppressive in the recruitment and functional aspects of these cells during an innate immune response. When peripheral human blood neutrophils were pretreated with exogenous opioids, lL-8-induced chemotaxis was inhibited (Grimm et al. 1998). Conversely, Simpkins et al. reported an increase in neutrophil chemotaxis... 

Taken together, the complexity by which morphine acts as an immunosuppressor on the migration and functional activity of innate immune responders, particularly neutrophils and macrophages, poses a compromising environment that proves detrimental for the hosts ability to eradicate pathogens. 

Welters ID, Menzebach A, Goumon Y, Cadet P, Menges T, Hughes TK, Hempelmann G, Stefano GB Morphine inhibits NF-kB nuclear binding in human neutrophils and monocytes by a nitric oxide-dependent mechanism. Anesthesiology 2000 92 1677-1684. 

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