Figure 1.
The design of animal study. In the early treatment protocol, there were
sham-operated rats, SU5416 combined with left pneumonectomy rats
(SuPNx42), and SuPNx42 rats given with
15 mg DIZE /kg/day from day 1 to day 42
(SuPNx42/DIZE1-42). In the late
treatment protocol, there were sham-operated rats (sham42),
SuPNx42, and a SuPNx42 rats given with
15 mg DIZE /kg/day from day 29 to day 42
(SuPNx42/DIZE29-42)
SuPNx: Su5416 with left pneumonectomy
DIZE: diminazene aceturate
Figure 2 Comparison of (A) right ventricle systolic pressure
(RVSP), (B) Fulton index, the weight ratio of right ventricle to left
ventricle plus septum, (RV/LV+S), (C) the lung weight and (D) the body
weight among the sham42, SuPNx42,
SuPNx42/DIZE1-42 and
SuPNx42/DIZE29-42 groups. RVSP levels
were significantly higher in the SuPNx42 group (45.17 ±
4.62 mmHg) than in sham-operated rats. (18.37 ± 1.36 mmHg,p <0.001) Both DIZE treatment groups
(SuPNx42/DIZE1–42 and
SuPNx42/DIZE29–42) showed significant
decreases in RVSP when compared with that of the SuPNx42rats. (early, 25.10 ± 1.38 mmHg, p <0.01; late 31.23 ±
4.06 mmHg, p <0.05) The Fulton index was significantly
increased in the SuPNx42 group (0.55 ± 0.06 ) than in
sham-operated group (0.35 ± 0.04, p <0.05), but no
significant changes were observed in the
SuPNx42/DIZE1-42 and
SuPNx42/DIZE29-42 groups when compared
with the SuPNx42 group. There was no significant change
in either the lung or body weight in all groups. Values represent the
mean ± SEM. *P <0.05, **P <0.01,
***P <0.001
Figure 3 (A) The plasma brain natriuretic peptide (BNP) and (B)
RV BNP levels. The plasma BNP level was significantly higher in the
SuPNx42 rats than in sham-operated rats.( 130.2 ± 19.76
vs. 59.50 ± 7.74 pg/ml; P <0.001) Treatment with DIZE
for 42 days significantly lowered the plasma BNP levels when compared
with that of the vehicle-treated group.(31.14 ± 2.83 vs. 130.2 ± 19.76
pg/ml; P <0.05) There was a trend that the
SuPNx42/DIZE29–42 rats had a decreased
plasma BNP level when compared with the SuPNx42 rats,
but the difference was not statistically significant. The RV BNP was
significantly higher in SuPNx42 rats than that of the
sham42 rats. (103.4 ± 10.01 vs. 31.05 ± 2.57 pg/ml;P <0.0001) Both DIZE treatment groups had significantly
lowered RV BNP than in the SuPNx42 rats. (early: 46.82 ±
6.62 pg/ml vs. 103.4± 10.01 pg/ml, P <0.0001; late:
61.83 ± 5.10 pg/ml vs. 103.4± 10.01 pg/ml, P <0.001)
Values represent the mean ± SEM. *P <0.05;
***P <0.001, ****P <0.0001
Figure 4 The representative results of Hematoxylin-eosin
stating of lung tissue (A), Verhoeff-van Gieson staining (B), and double
immunohistochemical staining of smooth muscle actin (green) and PCNA
(brown) (C). (D) The ratio of medial wall thickness of pulmonary
arterioles. The value for the sham42 group was set at
1.0. The muscular layer of pulmonary arterioles (50–100 μm in diameter)
was significantly thicker in the SuPNx42 rats than in
sham42,
SuPNx42/DIZE1-42, but not
SuPNx42/DIZE29–42 rats. (E) the
vascular occlusion score (VOS). The VOS of early treatment group
(SuPNx42/DIZE1-42) was decreased
compared to SuPNx42.( 1.27 ± 0.74 vs. 1.07 ± 0.56)
(magnification, 200x. Values represent the mean ± SEM.
*P<0.05, **P<0.01.
Figure 5 (A) A representative Western blot of eNOS, ACE, ACE2,
and the MAS receptor in sham42, SuPNx42,SuPNx42/DIZE1-42 and
SuPNx42/DIZE29-42 rats. (B) The
normalized eNOS/actin ratio revealed the expression of eNOS was higher
in the SuPNx42/DIZE1–42 rats than in
SuPNx42 rats. (C) The normalized ratio of ACE/actin
showed that the expression of ACE was higher in SuPNx42rats than in sham42 rats. DIZE administration decreased
ACE expression in the early treatment
(SuPNx42/DIZE1–42) and the late
treatment (SuPNX42/DIZE29–42) groups.
(D) The normalized ratio of ACE2/actin revealed that an increase in the
early treatment group
(SuPNX42/DIZE1–42) compared to the
SuPNx42 rats. No significant differences were found
among the sham42, SuPNx42, and
SuPNX42/DIZE29–42 groups. (E) The
normalized MAS/actin ratios were not changed in the all groups. The
value for the sham42 group was set at 1.0 in Figures 5B
– 5E. Values represent the mean ± SEM *P <0.05,
**P <0.01
Figure 6 (A) The levels of RV Ang-(1-7). The level of RV
Ang-(1-7) was significantly higher in the SuPNx42/DIZE1–42 and SuPNx42/DIZE29–42 rats than in SuPNx42 rats.
(B) The levels of pulmonary Ang-(1-7). The expression of pulmonary
Ang-(1-7) was significantly higher in SuPNx42/DIZE1–42 rats than in SuPNx42 rats.
Values represent the mean ± SEM. *P <0.05
***P<0.001, ****P<0.0001