Strain differences in sucrose preference and in the consequences of unpredictable chronic mild stress.
Effects of unpredictable chronic mild stress (UCMS) on anhedonic-like behaviour, physical state, body weight, learning and memory were investigated in three strains of mice. These strains were chosen among 11 strains that were tested in a first experiment for their sucrose consumption and preference for sucrose solutions of different concentrations. In the second experiment, groups of mice of the CBA/H, C57BL/6 and DBA/2 strains were submitted to 7 weeks of UCMS. Measures of the sucrose consumption, the evaluation of the physical state and the measurement of body weight were weekly assessed. Following 4-week period of UCMS, sub-groups of stressed and non-stressed mice were submitted to the spontaneous alternation test in the Y-maze, and then to the water-maze test for spatial learning and memory. UCMS induced a significant decrease of the sucrose consumption in CBA/H and in C57BL/6 but not in DBA/2 mice. The UCMS effect on sucrose intake in CBA/H mice was associated with a body weight loss and a physical state degradation. Spatial learning in a water maze was not disturbed by UCMS, however, a long-term memory impairment was observed in CBA/H stressed mice during a probe test. In the Y-maze, UCMS did not modify spontaneous alternation. These results show both an anhedonic-like and an amnesic effect of UCMS in CBA/H mice. They also reveal a difference of sensitivity to UCMS according to the strain of mice.
KEY-OBS SA, Parc Technologique, 3 allée du Titane, 16 rue Leonard de Vinci, 45100 Orleans, France. stephanie.pothion@wanadoo.fr
Stéphanie
S
Pothion
Jean-Charles
JC
Bizot
Fabrice
F
Trovero
Catherine
C
Belzung
D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal; D016009:Chi-Square Distribution; D002908:Chronic Disease; D003216:Conditioning, Operant / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004327:Drinking Behavior / Q000502:physiology*; D005106:Exploratory Behavior / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D008815:Mice, Inbred Strains; D013045:Species Specificity; D013315:Stress, Psychological / Q000503:physiopathology*; D013395:Sucrose / Q000494:pharmacology*; D013997:Time Factors
D013395:Sucrose