TIMP3 and triple-A syndrome: Other differences noted included the following: decreased AAA severity (Figure 4C), lowered abdominal aortic miR-181b expression by quantitative polymerase chain reaction (40%; Figure 4D), increased TIMP-3 protein expression (Figure 4E), significantly smaller mean maximal abdominal aortic diameters from histology (Figure 4F and 4G), and markedly more elastin (Figure 4G and 4H).