Table 1.
In vitro sensitivity to Ach and maximum relaxation response of aortas from young (2 months) and old (18 months) male and female mice treated with isoproterenol.
| Young (2 months old) | Old (18 months old) | |||
|---|---|---|---|---|
| pEC50 | Emax (%) | pEC50 | Emax (%) | |
| MALES | ||||
| Vehicle | 6.24 ± 0.03 | 76.7 ± 0.9 | ND | ND |
| ISO 5 μg/g/d | 6.13 ± 0.13 | 49.7 ± 2.7* | 6.01 ± 0.02 | 42.5 ± 0.4* |
| ISO 40 μg/g/d | 6.45 ± 0.23 | 31.3 ± 2.9* | 5.47 ± 0.07 | 40.4 ± 1.7*# |
| ISO 80 μg/g/d | 5.94 ± 0.16 | 39.4 ± 1.9* | 6.02 ± 0.05 | 50.9 ± 1.3*# |
| ISO 160 μg/g/d | 5.88 ± 0.21 | 34.3 ± 3.5* | ND | ND |
| FEMALES | ||||
| Vehicle | 6.02 ± 0.01 | 71.6 ± 0.4 | 6.29 ± 0.10 | 50.0 ± 2.2&# |
| ISO 5 μg/g/d | 5.54 ± 0.10* | 50.4 ± 2.8* | 6.13 ± 0.20# | 33.4 ± 2.8*&# |
| ISO 40 μg/g/d | 6.47 ± 0.15 | 49.9 ± 3.0*& | 6.23 ± 0.13& | 40.1 ± 2.6*# |
| ISO 80 μg/g/d | 6.18 ± 0.12 | 49.8 ± 2.6* | 5.94 ± 0.07 | 28.0 ± 1.2*&# |
| ISO 160 μg/g/d | 5.82 ± 0.16 | 48.2 ± 3.9*& | 6.02 ± 0.12 | 20.6 ± 1.2*&# |
Values are means ± SEM, n = 6–8 vasoreactivity assays. Aortas were pre-constricted with NE 1 μM. ISO doses were 5, 40, 80, and 160 μg/g/d for 7 days. pEC50 (–log10 de EC50), sensitivity to Ach; Emax, maximum relaxation response; ISO, isoproterenol; ND, not detected.
*
p < 0.05 vs. vehicle same group;
&
p < 0.05 vs. male same age and dose;
#
p < 0.05 vs. young same sex and dose determined by Student's t-test (controls) and two-way ANOVA and post hoc tests.