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9.4 Synthesis of leukotrienes and other lipoxygenase products by blood cells of the rainbow trout, Salmo gairdneri
Regulation by endocrine factors
441
enhance, the PMA- induced superoxide production by macrophages and neutrophils. These studies provide strong evidence that the autonomic nervous system plays a role in the regulation of teleost immunity. 9.4
S Y N T H E S I S OF L E U K O T R I E N E S A N D O T H E R L I P O X Y G E N A S E P R O D U C T S B L O O D C E L L S O F T H E R A I N B O W TROUT, S A L M O G A I R D N E R I
BY
T.R. Pettitt, A.F. Rowley and "Susan E. Barrow, Biomedical & Physiological Research Group, School of Biological Sciences, University College of Swansea, Singleton Park, Swansea, SA2 8PP: and Department of Clinical Pharmacology, Royal Postgraduate Medical School, Ducane Road, London W I 2 0 H S , UK. Leukotrienes are an important group of fatty acid derivatives, which act as pro-inflammatory molecules and immunomediators. Stimulation of whole blood from rainbow trout with 20 ~m calcium ionophore A23187 caused the production of leukotrienes B4 and BS, both at levels in excess of 10ng/ml blood. Their identification and quantification was achieved using reverse-phase high performance liquid chromatography, combined capillary column gas chromatograph-negative ion chemical ionization mass spectrometry and ultra violet spectroscopy. A number of other lipoxygenase products were also detected and partially analysed. The fatty acid composition of the leucocytes, which are presumed to be the site of leukotriene synthesis, was determined by thin-layer and gasliquid chromatography to enable a comparison of the relative levels of the polyunsaturated fatty acids which act as substrates for the synthesis of these lipoxygenase products. Arachidonic (20:4, n6), eicosapentaenoic (20:5, n-3) and docosahexaenoic (22:6, n-3) acids represented about 6, 5 and 40% respectively of the total fatty acid content. (Supported by SERC grant E.3130.7) 9.5
CATECHOLAMINE
REGULATION
O F A N D BY I M M U N I T Y
IN X E N O P U S
LAEVIS
R.H. Clothier, *L.N. Ruben, *K. Tran and Michael Balls, Department of Human Morphology, University of Nottingham, Nottingham NG7 2UH, UK; and Department of Biology, Reed College, Portland, OR 97202, USA. 6-hydroxydopamine chemically-sympathectomised adult Xenopus were tested for catecholamine regulation of anti-hapten (TNP-) responses. They were stimulated using TD, TI-I and TI-2 carriers, which activate different T and B cell populations in Xenopus. All immune responses were elevated, suggesting that catecholamines serve as general inhibitors of immune responses in the toad. LDopa, a dopamine agonist in vivo downregulates, while dopamine itself upregulates IL-2 receptor expression on PHA activated XenoDus splenocytes, as monitored by flow cytometric analyses of the binding of F1 -mouse anti-human IL-2 receptor antibody (B-D, 2A3) using PBS-azide membrane stabilised splenocytes. The bidirectionality of these putative regulatory interactions was also
441
enhance, the PMA- induced superoxide production by macrophages and neutrophils. These studies provide strong evidence that the autonomic nervous system plays a role in the regulation of teleost immunity. 9.4
S Y N T H E S I S OF L E U K O T R I E N E S A N D O T H E R L I P O X Y G E N A S E P R O D U C T S B L O O D C E L L S O F T H E R A I N B O W TROUT, S A L M O G A I R D N E R I
BY
T.R. Pettitt, A.F. Rowley and "Susan E. Barrow, Biomedical & Physiological Research Group, School of Biological Sciences, University College of Swansea, Singleton Park, Swansea, SA2 8PP: and Department of Clinical Pharmacology, Royal Postgraduate Medical School, Ducane Road, London W I 2 0 H S , UK. Leukotrienes are an important group of fatty acid derivatives, which act as pro-inflammatory molecules and immunomediators. Stimulation of whole blood from rainbow trout with 20 ~m calcium ionophore A23187 caused the production of leukotrienes B4 and BS, both at levels in excess of 10ng/ml blood. Their identification and quantification was achieved using reverse-phase high performance liquid chromatography, combined capillary column gas chromatograph-negative ion chemical ionization mass spectrometry and ultra violet spectroscopy. A number of other lipoxygenase products were also detected and partially analysed. The fatty acid composition of the leucocytes, which are presumed to be the site of leukotriene synthesis, was determined by thin-layer and gasliquid chromatography to enable a comparison of the relative levels of the polyunsaturated fatty acids which act as substrates for the synthesis of these lipoxygenase products. Arachidonic (20:4, n6), eicosapentaenoic (20:5, n-3) and docosahexaenoic (22:6, n-3) acids represented about 6, 5 and 40% respectively of the total fatty acid content. (Supported by SERC grant E.3130.7) 9.5
CATECHOLAMINE
REGULATION
O F A N D BY I M M U N I T Y
IN X E N O P U S
LAEVIS
R.H. Clothier, *L.N. Ruben, *K. Tran and Michael Balls, Department of Human Morphology, University of Nottingham, Nottingham NG7 2UH, UK; and Department of Biology, Reed College, Portland, OR 97202, USA. 6-hydroxydopamine chemically-sympathectomised adult Xenopus were tested for catecholamine regulation of anti-hapten (TNP-) responses. They were stimulated using TD, TI-I and TI-2 carriers, which activate different T and B cell populations in Xenopus. All immune responses were elevated, suggesting that catecholamines serve as general inhibitors of immune responses in the toad. LDopa, a dopamine agonist in vivo downregulates, while dopamine itself upregulates IL-2 receptor expression on PHA activated XenoDus splenocytes, as monitored by flow cytometric analyses of the binding of F1 -mouse anti-human IL-2 receptor antibody (B-D, 2A3) using PBS-azide membrane stabilised splenocytes. The bidirectionality of these putative regulatory interactions was also