Depression of lymphocyte traffic in sheep by anaesthesia and associated changes in efferent-lymph PGE2 and antibody levels.

General anaesthesia of sheep with ketamine and xylazine has been found to produce a profound and prolonged depression in lymphocyte traffic through primary peripheral lymph nodes, as mirrored in the output of lymphocytes into efferent lymph. In this study, the depression has been found to be associated with a marked and sustained elevation in prostaglandin E2 (PGE2) levels in efferent lymph. The degree and duration of lymphocyte output depression was found to be modulated (diminished), both in degree and duration, by study-node drainage-area stimulation from prior surgery, inflammation or bacterial immunization. Even when the anaesthesia-associated lymphocyte-output depression was modulated by drainage-area inflammation, the period of lymphocyte-output depression was correlated still with elevated levels of PGE2 in efferent lymph. When drainage-area stimulation was produced by bacterial immunization (killed Salmonella muenchen), the anaesthesia-associated depression in lymphocyte output into efferent lymph (small as well as blast) was accompanied by a depression in antibody output into efferent lymph.