Glucocorticoid involvement in suppression of NK activity following surgery in rats.
We studied plasma factors mediating suppression of NK activity (NKA) following surgery. Plasma from operated rats suppressed NKA of splenocytes, leukocytes, and purified natural killer (NK) cells, and charcoal stripping nullified suppression. The glucocorticoid antagonist mifepristone prevented suppression, whereas blockers of reactive oxygen metabolites, opioids, catecholamines, prostaglandin-E2, and histamine did not. NKA dropped as corticosterone levels peaked postoperatively, and administration of relevant doses of corticosterone suppressed NKA. Inhibition of glucocorticoid synthesis prevented plasma from suppressing NKA but merely attenuated NKA suppression in operated rats. Thus, postoperative concentrations of corticosterone can directly suppress NKA but additional factors probably act in vivo.
Neuroimmunomodulation Research Unit, Department of Psychology, Tel Aviv University, Tel Aviv 69978, Israel. shakhar@saturn.med.nyu.edu
Guy
G
Shakhar
Barak
B
Blumenfeld
D000527:Alprostadil / Q000276:immunology; D000818:Animals; D002927:Cimetidine / Q000097:blood / Q000494:pharmacology; D003345:Corticosterone / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000097:blood / Q000502:physiology; D003602:Cytotoxicity, Immunologic / Q000187:drug effects / Q000502:physiology*; D015232:Dinoprostone / Q000276:immunology; D005938:Glucocorticoids / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000097:blood / Q000502:physiology*; D007106:Immune Sera / Q000097:blood / Q000494:pharmacology; D007279:Injections, Subcutaneous; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology*; D007700:Kinetics; D007813:Laparotomy; D008297:Male; D015735:Mifepristone / Q000097:blood / Q000494:pharmacology; D011184:Postoperative Period; D051381:Rats; D011916:Rats, Inbred F344; D013491:Suppressor Factors, Immunologic / Q000037:antagonists & inhibitors / Q000096:biosynthesis / Q000097:blood / Q000502:physiology*; D014407:Tumor Cells, Cultured
D005938:Glucocorticoids; D007106:Immune Sera; D013491:Suppressor Factors, Immunologic; D015735:Mifepristone; D002927:Cimetidine; D000527:Alprostadil; D015232:Dinoprostone; D003345:Corticosterone