Mu and delta receptors mediate morphine effects on phagocytosis by murine peritoneal macrophages.

Studies with selective opioid agonists show that mu- and delta(2)-opioid receptors, but not kappa, are involved in opioid inhibition of phagocytosis in elicited murine macrophages. All mu and delta(2) agonists tested had similar maximal effects on phagocytosis, and all dose-response curves suggest positive cooperativity. In addition, mu and delta antagonists antagonized the effect of both mu and delta agonists.

[Obstructive syndrome caused by trichobezoars: historical disease or disease still current? Description of a case in adolescence].

Trichobezoars are masses of entangled material, found in the stomach and intestines, composed of hair ingested by the patient. When the mass grows, symptoms of intestinal occlusion can appear. Trichobezoars in pediatrics are usually found in adolescent females presenting personality disorders and trichophagia.

Reversibility of morphine effects on phagocytosis by murine macrophages.

Proneness of addicts to infections may be partially due to opiate effects on immune cells. We find that acute morphine inhibits phagocytosis in murine peritoneal macrophages in vitro with apparent desensitization at high concentrations, whereas chronic exposure results in a state akin to tolerance/dependence where macrophages seem to require morphine to phagocytize at a control level. However, both putative desensitization and tolerance/dependence are reversible, since drug re-addition several hours after withdrawal results in inhibition, as in acute exposure.