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Fig. 4. Cx37 immunostaining is detectable in the medial layer of mouse aorta as
well as in endothelium. Sections of thoracic aortas from 6-7-week-old
wild-type (A), Cx37/ (B) and
Cx40/ (C,D) mice were immunostained with anti-Cx37
antibody (A,B,C) or with secondary antibody only (D) and photographed at high
magnification. The lumen of the aorta is on the right in each panel. (A) In
wild-type aorta, very weak punctate staining was observed in the medial layer,
as well as strong endothelial staining. (B) The specificity of the medial
layer signal was confirmed by the absence of medial layer staining in
Cx37/ aortic sections. (C) Medial layer Cx37 staining
was elevated in Cx40/ sections. (D) Secondary
antibody-only control showed no signal in the medial layer of
Cx40/ aorta. (E,F) Sections of wild-type and
Cx40/ aorta from 4-month-old mice were immunostained
for Cx37. In addition to endothelial signal, faint punctate Cx37 staining was
observed in the medial layer of wild-type sections. Medial layer Cx37 staining
was particularly evident in aortas from 4-month-old
Cx40/ mice. Bar, 20 µm.