title: Biphasic regulation of macrophage attachment by activators of cyclic adenosine monophosphate-dependent kinase and protein kinase C.
abstract: A method is described that enabled us to study the adhesiveness of J-774 murine macrophages. Cell attachment was stimulated by activators of kinase C (i.e., phorbol esters) as well as kinase A (cyclic adenosine monophosphate; cAMP). This novel effect of cAMP was observed when its levels were increased via receptor triggering (prostaglandin E1, beta-adrenergic agonists), activation of Ns (cholera toxin), or inhibition of phosphodiesterase (Ro 20-1724) or when the kinase was directly activated by Br8-cAMP. The simultaneous treatment with kinase A and kinase C activators at the time of attachment resulted in a partially additive response. On the other hand, preincubation of the cells in suspension with one of the activators rendered them refractory to subsequent stimulation at the onset of the adhesion assay, whatever agent was used. Such a refractoriness was also observed in cells preincubated with oleoyl-acetyl-glycerol (OAG). On the other hand, when added at the time of attachment, this near-physiological activator of kinase C evoked a biphasic response: the early stimulation of cell attachment was followed by an accelerated rate of "detachment." In conclusion, kinase C and kinase A play a role in the sequence of events leading to cell adhesion. The cross desensitization observed is distal and takes place at or beyond the kinase step.
authors.affiliation: Unité 282 INSERM, Hôpital Henri Mondor, Créteil, France.
authors.forename: C
authors.initials: C
authors.lastname: Issaad
authors.forename: M A
authors.initials: MA
authors.lastname: Ventura
authors.forename: P
authors.initials: P
authors.lastname: Thomopoulos
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002772:Cholera Toxin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D004075:Diglycerides / Q000494:pharmacology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology*; D008264:Macrophages / Q000473:pathology* / Q000503:physiopathology; D051379:Mice; D015240:Phorbol 12,13-Dibutyrate / Q000494:pharmacology; D011493:Protein Kinase C / Q000378:metabolism / Q000494:pharmacology*; D011494:Protein Kinases / Q000494:pharmacology*; D012513:Sarcoma, Experimental / Q000473:pathology; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology
chemical_list: D004075:Diglycerides; D015124:8-Bromo Cyclic Adenosine Monophosphate; D015240:Phorbol 12,13-Dibutyrate; C038237:1-oleoyl-2-acetylglycerol; D002772:Cholera Toxin; D000242:Cyclic AMP; D011494:Protein Kinases; D011493:Protein Kinase C