Comparison of Systolic Blood Pressure and Heart Weight between S Rats and Congenic Strains for Chromosomes 1, 5, 10, and 17
| Strains | t-test probability | ||
| S | S. LEW(chr1) congenic | ||
| Blood pressure (mmHg) | 207 ± 2.2 | 181 ± 1.3 | <0.0001 |
| Body weight (grams) | 302 ± 1.8 | 300 ± 2.7 | 0.78 |
| Heart weight (grams) | 1233 ± 10.9 | 1107 ± 7.7 | <0.0001 |
| No. | 46 | 39 | |
| S | S. LEW(chr5) congenic | ||
| Blood pressure (mmHg) | 216 ± 2.4 | 201 ± 2.0 | <0.0001 |
| Body weight (grams) | 304 ± 1.6 | 282 ± 1.8 | <0.0001 |
| Heart weight (mg) | 1235 ± 7.9 | 1073 ± 9.2 | <0.0001 |
| Heart weight, body weight adjusted (mg)[ii] | 1178 ± 9.3 | 1130 ± 7.3 | <0.001 |
| No. | 40 | 40 | |
| S | S. LEW(chr10) congenic | ||
| Blood pressure (mmHg) | 219 ± 3.4 | 177 ± 2.1 | <0.0001 |
| Body weight (grams) | 290 ± 1.9 | 292 ± 2.1 | 0.36 |
| Heart weight (mg) | 1206 ± 15.5 | 1096 ± 11.6 | <0.0001 |
| No. | 20 | 20 | |
| S | S. LEW(chr17) congenic | ||
| Blood pressure (mmHg) | 205 ± 5.9 | 210 ± 3.7 | 0.43 |
| Body weight (grams) | 299 ± 4.0 | 287 ± 2.2 | 0.013 |
| Heart weight (mg) | 1211 ± 17.1 | 1189 ± 15.3 | 0.34 |
| Heart weight, body weight adjusted (mg)[ii] | 1197 ± 14.1 | 1204 ± 13.9 | 0.72 |
| No. | 19 | 20 | |
[i] Means ± S.E. are presented. S and a congenic strain to be compared were bred and raised concomitantly and fed on a 2% NaCl diet for 24 days starting at age 40–44 days. For the comparisons involving S vs. S. LEW(chr1) and S vs. S. LEW(chr5), two independent tests (20 rats per strain) were made, and in both comparisons both independent tests showed significant differences for blood pressure (all at least <0.002); combined data for both tests (40 rats per strain) are shown. For the S vs. S. LEW(chr17) and S vs. S. LEW(chr10) comparisons one test was made.
[ii] Heart weight adjusted for differences in body weight using the regression of heart weight on body weight.