Table 4.
Effects of i.c.v. Ucn 2 on 7 h meal microstructure in genetically selected DIO and DR rats
| Parameter | 0–2 h | 2–7 h | 0–7 h | |||
|---|---|---|---|---|---|---|
| DR | DIO | DR | DIO | DR | DIO | |
| Feeding | ||||||
| Avg meal size (g) | ||||||
| ANOVA | — | # | — | — | # | ## |
| Linear contrast | — | † | † | † | †† | †† |
| 0 μg | 2.6 ± 0.3 | 3.0 ± 0.5 | 2.6 ± 0.2 | 2.1 ± 0.3 | 2.5 ± 0.1 | 2.3 ± 0.3 |
| 0.3 μg | 2.6 ± 0.4 | 3.2 ± 0.7 | 2.2 ± 0.3 | 1.8 ± 0.2 | 2.4 ± 0.2 | 2.2 ± 0.3 |
| 1 μg | 1.8 ± 0.3 | 1.7 ± 0.4 | 1.7 ± 0.3 | 1.3 ± 0.2 | 1.8 ± 0.2* | 1.5 ± 0.2* |
| 3 μg | 2.3 ± 0.4 | 1.3 ± 0.3* | 1.5 ± 0.3 | 1.1 ± 0.2 | 1.8 ± 0.2* | 1.2 ± 0.2* |
| Meal frequency (min) | ||||||
| ANOVA | — | — | — | — | — | — |
| Linear contrast | — | — | — | — | — | — |
| 0 μg | 1.9 ± 0.3 | 2.5 ± 0.4 | 2.7 ± 0.2 | 2.8 ± 0.5 | 4.6 ± 0.3 | 5.3 ± 0.5 |
| 0.3 μg | 2.1 ± 0.3 | 2.4 ± 0.4 | 1.8 ± 0.3 | 2.6 ± 0.6 | 3.9 ± 0.5 | 5.0 ± 0.6 |
| 1 μg | 2.1 ± 0.1 | 2.5 ± 0.2 | 2.3 ± 0.4 | 3.0 ± 0.4 | 4.4 ± 0.4 | 5.5 ± 0.4 |
| 3 μg | 1.8 ± 0.2 | 3.0 ± 0.5 | 2.3 ± 0.4 | 2.5 ± 0.4 | 4.1 ± 0.5 | 5.5 ± 0.7 |
| Avg intermeal interval (min) | ||||||
| ANOVA | — | — | — | — | — | — |
| Linear contrast | — | — | — | — | — | — |
| 0 μg | 43.5 + 7.8 | 22.4 + 3.5 | 102.5 + 10.9 | 70.8 + 29.0 | 83.0 + 8.2 | 63.9 + 14.2 |
| 0.3 μg | 45.4 + 11.3 | 28.6 + 7.1 | 94.8 + 15.6 | 69.5 + 27.3 | 104.4 + 22.0 | 65.8 + 14.4 |
| 1 μg | 51.5 + 4.4 | 30.5 + 6.3 | 104.8 + 22.5 | 85.6 + 16.1 | 79.1 + 9.0 | 68.8 + 3.8 |
| 3 μg | 44.8 + 5.3 | 19.6 + 2.8 | 91.8 + 25.4 | 69.2 + 19.6 | 96.3 + 21.1 | 65.1 + 14.9 |
| Avg meal duration (min) | ||||||
| ANOVA | — | — | — | — | # | — |
| Linear contrast | — | † | — | — | †† | † |
| 0 μg | 11.6 ± 1.2 | 11.3 ± 1.8 | 11.7 ± 0.8 | 8.7 ± 1.9 | 11.2 ± 0.7 | 9.2 ± 1.2 |
| 0.3 μg | 12.1 ± 1.8 | 12.3 ± 2.7 | 11.3 ± 1.9 | 6.7 ± 1.0 | 11.6 ± 1.3 | 8.2 ± 1.0 |
| 1 μg | 8.8 ± 1.8 | 7.0 ± 1.5 | 8.4 ± 1.5 | 5.9 ± 0.8 | 8.5 ± 1.3* | 6.5 ± 0.8 |
| 3 μg | 10.5 ± 0.9 | 5.2 ± 0.8 | 7.4 ± 1.6 | 6.4 ± 1.1 | 8.5 ± 0.8* | 6.1 ± 0.7 |
| Eating rate (mg s−1) | ||||||
| ANOVA | — | — | — | — | — | # |
| Linear contrast | — | — | — | — | — | †† |
| 0 μg | 3.8 ± 0.3 | 4.4 ± 0.3 | 3.8 ± 0.3 | 4.4 ± 0.4 | 3.8 ± 0.3 | 4.4 ± 0.3 |
| 0.3 μg | 3.7 ± 0.3 | 4.4 ± 0.3 | 3.5 ± 0.3 | 4.6 ± 0.3 | 3.6 ± 0.3 | 4.3 ± 0.3 |
| 1 μg | 3.7 ± 0.4 | 3.8 ± 0.4 | 3.6 ± 0.4 | 3.9 ± 0.5 | 3.7 ± 0.3 | 3.8 ± 0.4 |
| 3 μg | 3.6 ± 0.3 | 4.0 ± 0.4 | 5.5 ± 2.1 | 3.2 ± 0.6 | 3.6 ± 0.3 | 3.5 ± 0.5 |
| Drinking Avg meal size (ml) | ||||||
| ANOVA | # | — | ## | — | ### | # |
| Linear contrast | †† | † | †† | † | ††† | †† |
| 0 μg | 1.8 ± 0.5 | 2.3 ± 0.6 | 2.9 ± 0.4 | 2.3 ± 0.4 | 2.5 ± 0.4 | 2.1 ± 0.4 |
| 0.3 μg | 1.4 ± 0.5 | 2.3 ± 0.5 | 2.7 ± 0.7 | 2.1 ± 0.3 | 2.0 ± 0.5 | 2.0 ± 0.2 |
| 1 μg | 1.1 ± 0.4 | 1.4 ± 0.4 | 1.4 ± 0.4* | 1.1 ± 0.4 | 1.3 ± 0.3** | 1.2 ± 0.3 |
| 3 μg | 0.7 ± 0.2* | 0.9 ± 0.3 | 1.3 ± 0.4* | 0.9 ± 0.3 | 1.0 ± 0.2*** | 1.0 ± 0.2 |
| Avg meal duration (min) | ||||||
| ANOVA | — | # | — | — | # | # |
| Linear contrast | — | †† | † | † | † | †† |
| 0 μg | 4.0 ± 0.9 | 6.2 ± 2.0 | 4.4 ± 0.6 | 6.8 ± 1.6 | 4.2 ± 0.6 | 5.7 ± 1.5 |
| 0.3 μg | 2.5 ± 0.7 | 8.3 ± 2.7 | 4.0 ± 1.0 | 4.6 ± 0.9 | 3.2 ± 0.7 | 5.5 ± 0.7 |
| 1 μg | 2.9 ± 0.7 | 3.4 ± 0.9 | 2.3 ± 0.7 | 2.8 ± 1.0 | 2.7 ± 0.5 | 3.0 ± 0.5 |
| 3 μg | 1.8 ± 0.8 | 1.6 ± 0.6 | 2.3 ± 0.5 | 2.5 ± 1.1 | 1.8 ± 0.4 | 2.4 ± 0.7 |
| Drinking rate (μl s−1) | ||||||
| ANOVA | — | — | — | — | — | — |
| Linear contrast | — | — | — | — | — | — |
| 0 μg | 8.5 ± 1.2 | 10.5 ± 3.2 | 11.1 ± 0.6 | 6.3 ± 0.9 | 10.2 ± 0.7 | 6.8 ± 1.0 |
| 0.3 μg | 9.7 ± 1.0 | 5.6 ± 0.9 | 11.5 ± 0.4 | 7.8 ± 0.6 | 10.4 ± 1.0 | 6.3 ± 0.6 |
| 1 μg | 7.2 ± 1.8 | 9.3 ± 3.3 | 14.0 ± 3.5 | 9.0 ± 1.5 | 7.8 ± 1.5 | 5.9 ± 0.9 |
| 3 μg | 15.2 ± 4.7 | 10.2 ± 1.8 | 10.8 ± 1.7 | 12.6 ± 3.4 | 14.4 ± 4.7 | 13.8 ± 5.4 |
Effect of third ventricle Ucn 2 treatment on nocturnal meal microstructure of genetically selected diet-induced obesity-resistant (DR) and susceptible (DIO) rats. Data express the mean ± s.e.m. of several meal microstructure measures of adult male DR (n = 9) and DIO (n = 8) rats during the first 7 h of the dark cycle following central Ucn 2 pretreatment. Subjects were pretreated (−10 min) with Ucn 2 in a balanced Latin square design with test sessions beginning at the onset of the dark cycle. Avg = average. Symbols denote significant differences:
P < 0.05
P < 0.01
P < 0.001 from the respective vehicle condition (within-subject Newman–Keuls test)
P < 0.05
P < 0.01
P < 0.001 denote a significant dose effect of Ucn 2 (ANOVA)
P < 0.05
P < 0.01
P < 0.001 denote a significant log-linear, dose-dependent effect of Ucn 2 (Linear contrast ANOVA).