Figure 1.
Experimental overview of the pilot study.
CORT: corticosterone; OGTT: oral glucose tolerance test.
Figure 2.
Schematic diagram of the different stages of the main study.
BS: blood sample; CORT: corticosterone; EZM: elevated zero maze; FST: forced swimming test; OF: open field test.
Figure 3.
Effects of CORT treatment orally via the drinking water or by daily s.c. injection upon body weight (mean % change compared to body weight prior to start of treatment+S.E.M.) during the 4 week treatment period and 1 and 2 weeks after treatment cessation (week 5 and 6).
The figure shows significant increased body weights in the group receiving CORT via the drinking water compared to the vehicle drinking water group (#) or CORT injection group (*). #/*P<0.05.
Figure 4.
Plasma glucose levels (mean % change from baseline+S.E.M.) after acute glucose challenge in fasted animals receiving corticosterone (CORT) or vehicle either orally via the drinking water or by daily s.c. injection as measured by oral glucose tolerance tests (OGGT).
Within each OGTT, plasma glucose levels are measured at baseline (0) and 15, 30, 60 and 120 min after an oral administration of glucose. Treatment effects upon glucose tolerance were measured at 3 time-points throughout the experiment, namely directly after 4 weeks treatment (OGTT1) and 1 and 2 weeks after treatment cessation (OGTT2, OGTT3, respectively). (*) trend; P = 0.094.
Table 1.
Mean (± S.E.M.) fasting blood glucose (mmol/l), plasma insulin (ng/ml) values and HOMA-IR index directly after 4 weeks treatment via drinking water (t1) and 1 (t2) and 2 weeks (t3) after treatment cessation.
Figure 5.
Effects of corticosterone (CORT) administration via the drinking water upon body weight (mean % change compared to body weight prior to start of treatment+S.E.M.) during the 12 week treatment period.
Significant increased body weights in the CORT group are denoted with * (P<0.01); (*) trend.
Figure 6.
Effects of corticosterone (CORT) administration via the drinking water upon water intake (mean % change+S.E.M.) during the 12 week treatment period.
Significant increased amounts of water intake in the CORT group are denoted with *(P<0.01).
Table 2.
Mean (± S.E.M.) fasting blood glucose (mmol/l), plasma insulin (ng/ml) values and HOMA-IR index at baseline (t0), after 4 weeks (t1) and after 12 weeks treatment (t2).
Figure 7.
Effect of CORT administration via the drinking water (mean+S.E.M.) upon total distance moved and % time spent in the open arms of the elevated zero maze (EZM).
(*) Trend towards difference between CORT and vehicle treatment (P = 0.09).
Figure 8.
Effect of corticosterone (CORT) administration via the drinking water (mean+S.E.M.) upon total distance moved, body weight at time of testing and total immobility time in the forced swim test (FST).
*Significant difference between CORT and vehicle treatment (P<0.01).
Figure 9.
Effect of corticosterone (CORT) administration via the drinking water (mean+S.E.M.) upon total distance moved, body weight at time of testing and fecal boli production in the open field test (OF).
*Significant difference between CORT and vehicle treatment (P<0.01).