Effect of 5-HT on Adiposity of Mice Fed a High Fat Diet.

<p>A, Body weight of male C57BL/6 mice fed a chow diet (Ch) or a high fat diet (F) were measured over 26 weeks (n = 12 to 20). Mice were intraperitoneally injected with PBS or 5-HT (1 mg/mouse) twice a week. Open circles, chow plus PBS (Ch+PBS); filled circles, chow plus 5-HT (Ch+5HT); open squares, F diet plus PBS (F+PBS); filled squares, F diet plus 5-HT (F+5HT). B and C, Photographs are the gross appearance (B) and the abdominal cavity (C) of representative mice from each group at 26 weeks of age. D, The proportion of whole body fat (n = 5) and intraabdominal fat (n = 10) of each group of mice at 26 weeks of age. E, The adipose tissues of mice at 26 weeks of age were stained with hematoxylin and eosin. Bars in histological sections indicate 50 μm. Figs show the size distribution of adipocytes. Data are means ± s.d. Figs with a different superscript letter are significantly different (p<0.05). F, The change in body weight of C57BL/6 mice treated with several doses of 5-HT were measured over 22 weeks (n = 14 to 20). The body weight of mice at 22 weeks of age shows the concentration dependent effect of 5HT. Open circles, Ch+PBS; open squares, F+PBS; filled symbols, F+5HT at a concentration of 0.1 mg (▲), 0.5 mg (◆) and 1.0 mg/mouse (■). Red colored symbols show significance in F+5HT mice against F+PBS mice (p<0.05). Data are means ± s.e. All data were analyzed by two-way ANOVA without (F). Data in (F) was analyzed by one-way ANOVA. Columns with a different letter are significantly different (p<0.05). *p<0.05, **p<0.01 indicates significance in F+5HT mice against F+PBS mice.