AJP - Cell Physiology, Vol 261, Issue 3 C413-C416, Copyright © 1991 by American Physiological Society
Histamine H1-receptor-mediated keratan sulfate production in rabbit chondrocytes: involvement of protein kinase C
K. Fukuda, H. Yamasaki, Y. Nagata, H. Motoyoshi, F. Matsumura, T. Kuno and S. Tanaka
Department of Orthopedic Surgery, Kinki University School of Medicine, Osaka, Japan.
We investigated the characteristics of the histamine H1-receptor in
cultured rabbit chondrocytes. Scatchard analysis of [3H]pyrilamine, an
H1-antagonist, binding to the chondrocytes revealed a single class of
binding sites with KD and Bmax values of 90 +/- 12 nM and 56 +/- 11
fmol/10(4) cells, respectively. H1-agonists stimulated the production of
keratan sulfate in a dose-dependent manner. Stimulation of keratan sulfate
production was inhibited by pyrilamine. Protein kinase C inhibitors
(sphingosine and H-7) also had inhibitory effects. Phorbol
12,13-dibutyrate, a direct activator of protein kinase C, activated the
production. When protein kinase C in the chondrocytes was down-regulated by
preincubation with phorbol ester, the effect of the H1-agonist on keratan
sulfate production was abolished. These results indicate that the histamine
H1-receptor on chondrocytes mediates the accumulation of keratan sulfate
production and that protein kinase C is involved in these events.
