Fig. 6. Biocytin transfer is reduced in aortic endothelium of connexin-deficient mice. Biocytin and FITC-dextran were injected into endothelial cells of wild-type, Cx37^–/–, Cx40^–/– or Cx37^+/–Cx40^–/– thoracic aorta isolated from 6-7-week-old animals. Biocytin transfer was reduced in Cx37^–/– (C) and Cx40^–/– (E) endothelium compared with wild-type endothelium (A). Biocytin-containing cells in panel A extended beyond the photographic field of view. Transfer was further reduced in Cx37^+/–Cx40^–/– endothelium (G). FITC-dextran marked the injected cell, but did not transfer to adjacent cells. There was more autofluorescence in panels (B,F) than (D,H) because the FITC-dextran was photographed after fixing the tissue. Quantification is presented in Fig. 10 and Table 2. Bar, 50 µm.