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The ionophore A23187 (6.7 microM) increased the rates of formation of prostaglandins and cyclic AMP in suspensions of thioglycollate-elicited rat peritoneal macrophages. Both effects were inhibited by the calmodulin blocker trifluoperazine (50 microM) and the calcium channel blocker verapamil (500 microM). Inhibitors of phospholipase A2 and cyclo-oxygenase also blocked both actions of A23187. The stimulated prostaglandin formation was markedly reduced when the cells were preincubated with 8-bromo-cyclic AMP (1mM), dibutyryl cyclic AMP (1mM) or cholera toxin (500ng/ml). Addition of exogenous arachidonic acid (30 microM) alleviated this inhibition. We propose that the effect of A23187 on macrophages includes a 'self-limiting' mechanism whereby newly-synthesized prostaglandins can inhibit, via cyclic AMP, a step(s) prior to the transformation of arachidonic acid and thus modulate their own production.
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
September 1969,
Biochemical and biophysical research communications,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
January 1985,
Advances in prostaglandin, thromboxane, and leukotriene research,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
August 1988,
Immunology,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
January 1981,
Scandinavian journal of rheumatology. Supplement,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
May 1978,
Prostaglandins,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
January 1990,
Platelets,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
May 1974,
Prostaglandins,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
January 1979,
Experimental cell research,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
June 1973,
The Journal of laboratory and clinical medicine,
L K Lim, and
N H Hunt, and
R D Eichner, and
M J Weidemann
December 1980,
Agents and actions,
