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Fig. 3. Endothelial Cx37 immunostaining is markedly reduced in
Cx40/ aorta. Sections of thoracic aortas from E18.5
embryos (A-H) or 7-week-old mice (I-P) were immunostained for Cx37 or Cx40.
Differential interference contrast images are shown to the right of each
panel. In sections of aorta from E18.5 Cx40/ embryos
(C,D), endothelial Cx37 immunostaining was virtually absent, whereas
endothelial Cx37 staining was readily detected in wild-type sections (A,B).
Cx40 immunostaining in sections of E18.5 Cx37/ aorta
(G, H) was similar to that observed with sections of E18.5 wild-type aorta
(E,F). Sections of aorta from a 7-week-old Cx40/
animal showed a substantial reduction in endothelial Cx37 immunostaining (K,L)
compared with wild-type (I,J). Only rarely were punctate signals observed in
the endothelium. Cx40 immunostaining in sections of 7-week-old
Cx37/ aorta was slightly reduced (O,P) compared with
wild-type signals (M,N). En face immunostaining of segments of 7-week-old
aorta confirmed that endothelial Cx37 immunostaining was greatly reduced in
Cx40/ aortic segments (R) compared with wild-type
(Q). For the inset in panel R, the exposure level was adjusted to bring out
faint Cx37 immunostaining in the Cx40/ endothelium.
En face Cx40 staining was slightly reduced in Cx37/
aortic segments (T) compared with wild-type (S). Bars, 20 µm.