Central tumour necrosis factor-alpha mediates the early gastrointestinal motor disturbances induced by lipopolysaccharide in sheep.
Cytokines are involved in fever and other symptoms of the acute phase response induced by endotoxins. The aim of this work was to study the involvement of central tumour necrosis factor-alpha (TNF-alpha) in the changes induced by lipopolysaccharide (LPS) on gastrointestinal (GI) motility in sheep. Body temperature and myoelectric activity of the antrum, duodenum and jejunum was recorded continuously. Intravenous (i.v.) administration of LPS (0.1 micro g kg-1)-induced hyperthermia, decreased gastrointestinal myoelectric activity and increased the frequency of the migrating motor complex (MMC). These effects started 40-50 min after LPS and lasted for 6-7 h. TNF-alpha (50 and 100 ng kg-1) mimicked these effects when injected intracerebroventricularly (i.c.v.) but not i.v. Pretreatment with soluble recombinant TNF receptor (TNFR:Fc, 10 micro g kg-1, i.c.v.) abolished the TNF-induced actions and reduced those evoked by LPS. Furthermore, the effects induced by either LPS or TNF were suppressed by prior i.c.v. injection of indomethacin (100 micro g kg-1). In contrast, the i.v. injections of TNFR:Fc or indomethacin were ineffective. Our data suggest that LPS disturbs GI motility in sheep through a central pathway that involves TNF-alpha and prostaglandins sequentially.
Guerrero-Lindner
E
E
Department of Pharmacology and Physiology, Veterinary Faculty, University of Zaragoza, Zaragoza, Spain.
Castro
M
M
Muñoz
J M
JM
Arruebo
M P
MP
Murillo
M D
MD
Buéno
L
L
Plaza
M A
MA
D000818:Animals; D001831:Body Temperature / Q000187:drug effects; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D005260:Female; D005334:Fever / Q000139:chemically induced; D005769:Gastrointestinal Motility / Q000187:drug effects*; D006801:Humans; D007141:Immunoglobulin Fc Fragments; D007213:Indomethacin / Q000008:administration & dosage / Q000494:pharmacology; D007275:Injections, Intravenous; D007276:Injections, Intraventricular; D008070:Lipopolysaccharides / Q000494:pharmacology*; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D016065:Myoelectric Complex, Migrating / Q000187:drug effects; D018124:Receptors, Tumor Necrosis Factor / Q000008:administration & dosage; D011994:Recombinant Proteins; D034561:Sheep, Domestic; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage / Q000494:pharmacology*
D016861:Cyclooxygenase Inhibitors; D007141:Immunoglobulin Fc Fragments; D008070:Lipopolysaccharides; D018124:Receptors, Tumor Necrosis Factor; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D007213:Indomethacin