Interleukin-1 beta increases prostaglandin E2-stimulated adenosine 3',5'-cyclic monophosphate production in rabbit pigmented ciliary epithelium.
This study was designed to determine the effects of interleukin-1 on basal and prostaglandin E2-stimulated adenosine 3',5'-cyclic monophosphate production by primary and first passage cultures of non-transformed rabbit pigmented and non-pigmented ciliary epithelial cells. Confluent cultures of rabbit pigmented and non-pigmented ciliary epithelial cells were incubated for varying periods of time in serum-free medium with or without interleukin-1 beta, tumor necrosis factor-alpha, bacterial lipopolysaccharide, transforming growth factor-beta 2, cycloheximide, indomethacin and combinations of these agents. Cells were then preincubated for 10 min with serum-free medium plus the phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (for basal adenosine 3',5'-cyclic monophosphate production) or serum-free medium containing several concentrations of prostaglandin E2 and 3-isobutyl-1-methylxanthine. In certain experiments isoproterenol, vasoactive intestinal peptide, or forskolin was substituted for prostaglandin E2. Adenosine 3',5'-cyclic monophosphate was then extracted into ice-cold absolute ethanol and measured by radioimmunoassay. Prostaglandin E2 stimulated adenosine 3',5'-cyclic monophosphate production in pigmented and non-pigmented ciliary epithelial cells in a dose-dependent manner. Incubation with interleukin-1 beta (150 U ml-1) increased prostaglandin E2-stimulated, but not basal adenosine 3',5'-cyclic monophosphate production in pigmented ciliary epithelial cells. This interleukin-1 beta-induced enhancement of prostaglandin E2-stimulated adenosine 3',5'-cyclic monophosphate production, called the interleukin-1 effect, was not seen with non-pigmented ciliary epithelial cells. The interleukin-1 effect was dependent upon interleukin-1 beta concentration, time and de novo protein synthesis. The interleukin 1 effect could not be reproduced by replacing interleukin-1 beta with tumor necrosis factor-alpha or bacterial lipopolysaccharide and was specific for prostaglandin E2, since interleukin-1 beta did not enhance isoproterenol-, vasoactive intestinal peptide-, or forskolin-induced adenosine 3',5'-cyclic monophosphate production. Chronic exposure to prostaglandin E2 (during the 3 hr incubation period), with or without interleukin-1 beta in the incubation medium, reduced subsequent prostaglandin E2-stimulated adenosine 3',5'-cyclic monophosphate production. Inhibition of de novo prostaglandin synthesis with indomethacin increased the interleukin-1 effect. The interleukin-1 effect was inhibited by the immunosuppressive cytokine, transforming growth factor-beta 2, in a dose-dependent manner. This is the first report of prostaglandin E2-induced stimulation of adenosine 3',5'-cyclic monophosphate production by pigmented ciliary epithelial cells and of the unique ability of interleukin-1 to increase this effect. The results are consistent with interleukin-1-induced upregulation of prostaglandin E receptors. Since transforming growth factor-beta 2 inhibited this interleukin-1 effect, this immunosuppressive cytokine may exert negative feedback and thus regulate the physiological consequences of the interleukin-1 effect.
Fleisher
L N
LN
College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
McGahan
M C
MC
Ferrell
J B
JB
Pagan
I
I
D000818:Animals; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis*; D003513:Cycloheximide / Q000494:pharmacology; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000187:drug effects / Q000378:metabolism*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D011817:Rabbits; D013268:Stimulation, Chemical; D016212:Transforming Growth Factor beta / Q000494:pharmacology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology; D015854:Up-Regulation; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D016861:Cyclooxygenase Inhibitors; D007375:Interleukin-1; D008070:Lipopolysaccharides; D011500:Protein Synthesis Inhibitors; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D005576:Colforsin; D014660:Vasoactive Intestinal Peptide; D003513:Cycloheximide; D000242:Cyclic AMP; D015232:Dinoprostone; D007545:Isoproterenol; D007213:Indomethacin