Figure 4.

Sections of hearts from wild-type (+/+//+/+//+/+), AT_1a- (−/−//+/+//+/+), AT_1b- (+/+//−/−//+/+), and AT₂- (+/+//+/+//−/−) receptor single-knockout mice, mice exclusively expressing AT_1a (+/+//−/−//−/−), AT_1b (−/−//+/+//−/−), or AT₂ (−/−//−/−//+/+) receptors, triple-knockout mice (−/−//−/−//−/−), and angiotensinogen-deficient (Agt −/−) mice do not show changes in basal connective tissue production (van Gieson-stained; magnification: 400-fold; representative sections for all groups from n ≥ 4 sections).