Fig. 4.

A: Mardin Darby Canine Kidney (MDCK) cells contain Connexin43 (Cx43), which is found at sites of cell-cell contact (B). Treatment of 0.1 μM of IL-1β caused an internalization of Cx43, which was blocked by the IL-1β receptor antagonist IL-1ra (C). Dye spread studies showed that although control MDCK cells are highly coupled (D), IL-1β treatment caused a complete loss cell coupling (E). Inhibition of the IL-1β receptor with IL-1ra inhibited both the changes in Cx43 localization (C) and function (F). Treatment of rat neonatal myocytes (G) with 0.1 μM IL-1β (H) caused the same internalization of Cx43 as was seen in the MDCK cells that was also reversed by addition of the IL-1ra (I), suggesting that this effect of IL-1β is not cell type specific. J: quantification of the dye-spread studies (n = 3). Quantification of the level of Cx43 in cultured rat neonatal myocytes is seen in K. Values are reported as a percentage of normal.