Protein kinase C inhibitors enhance concanavalin A cap formation in polymorphonuclear leukocytes.
The potent protein kinase C (PKC) inhibitors, 1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride (H-7) and staurosporine, significantly enhanced concanavalin A (Con A)-induced cap formation in polymorphonuclear leukocytes (PMNs) from C57BL/6 mice after pretreatment for 30 min at concentrations of 10 microM and 1 nM, respectively. However, neither 10 microM of N-(2-aminoethyl)-5-isoquinolinesulfonamide dihydrochloride (H-9) nor N-(2-guanidinoethyl)-5-isoquinolinesulfonamide hydrochloride (HA1004), which inhibit cyclic nucleotide-dependent protein kinases more effectively than other kinases, affected the capping. Meanwhile, treatment of PMNs with Con A induced the translocation of PKC from the cytosol to the membrane fraction within 5 min, which is considered to be important for the activation of this enzyme. When cells were pretreated with H-7 or staurosporine for 30 min at the concentrations that enhanced the capping, both the cytosolic and the membrane-bound PKC activity was inhibited during the further incubation with Con A. These results suggest that PKC may play an important role in the regulation of Con A-induced cap formation in PMNs.
Sato
A
A
Department of Bacteriology, Fukushima Medical College, Japan.
Tanabe
F
F
Ito
M
M
Ishida
E
E
Shigeta
S
S
D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D000818:Animals; D003078:Colchicine / Q000494:pharmacology; D003208:Concanavalin A / Q000494:pharmacology*; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D005260:Female; D016650:Fluorescein-5-isothiocyanate; D005452:Fluoresceins / Q000378:metabolism; D066298:In Vitro Techniques; D007546:Isoquinolines / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000187:drug effects / Q000648:ultrastructure*; D010879:Piperazines / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors*; D013861:Thiocyanates / Q000378:metabolism
D005452:Fluoresceins; D007546:Isoquinolines; D010879:Piperazines; D013861:Thiocyanates; D003208:Concanavalin A; D019307:1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; D011493:Protein Kinase C; D016650:Fluorescein-5-isothiocyanate; D003078:Colchicine