title: Brain peptide reverses effect of morphine on human lymphocytes.
abstract: E-rosette formation by human lymphocytes incubated with sheep red blood cells (sRBC) is inhibited by morphine. We studied the ability of the opiate antagonists naloxone and Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) to block this action. Active E-rosette formation by lymphocytes incubated with morphine was reduced from the control of 35.7 +/- 1.7% to 23.7 +/- 1.5% (p less than 0.001). Similarly, total E-rosette formation was reduced by morphine from the control of 65.8 +/- 1.3% to 53.2 +/- 2.9% (p less than 0.001). These effects were blocked by co-incubation of the lymphocytes with either Tyr-MIF-1 or naloxone (p less than 0.05). Tyr-MIF-1 was active (p less than 0.05) at concentrations as dilute as 10(-13) M. These results indicate that the neuropeptide Tyr-MIF-1 exerts an antiopiate effect at the human T-lymphocyte.
mesh_terms: D000328:Adult; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology; D009075:MSH Release-Inhibiting Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D009020:Morphine / Q000037:antagonists & inhibitors*; D009270:Naloxone / Q000494:pharmacology; D012397:Rosette Formation
chemical_list: D009270:Naloxone; D009020:Morphine; C036930:tyrosyl-prolyl-leucyl-glycinamide; D009075:MSH Release-Inhibiting Hormone