These findings suggest that the primary target tissues of pika leptin are on body fat and not lean body mass. The mass of heart, lung and kidneys was not affected by leptin treatment or cold exposure (table 1). However, under warm acclimation spleen weight did not obviously change (Table 1). CP: 3.70 6 0.84 mg/ g p, 0.05 Table 1), whereas pika leptin could restore normality of spleen weight (CP: 3.70 6 0.84 mg/g vs. Interestingly, cold exposure also contributed to a reduction in spleen weight (WP: 7.18 6 1.26 mg/g vs. However, chronic cold exposure increased BAT weight (3.00 6 0.39 vs. Pika leptin treatment distinctly reduced BAT weight ((BAT weight/total body weight) 6 1000) compared to PBS-controls under both warm and cold temperatures (1.95 6 0.39 vs. BAT was another target organ affected by both pika leptin and cold exposure. Histomorphology of WAT confirmed that white adipocytes of mice treated by pika leptin exhibited a marked decrease in intercellular lipid accumulation smaller and fewer lipid droplets than those from PBS control mice (Figure 3). White adipose tissue (WAT) weight ((WAT weight / total body weight) 6 1000) decreased in warm and cold exposed mice receiving pika leptin (WL and CL respectively) compared to warm and cold exposed mice receiving PBS control (WP and CP respectively) (3.54 6 1.31 vs. Both pika leptin treatment and chronic cold exposure had significant effects on body composition, which presented as a distinct loss in body fat mass and not in lean body mass. To further explore the reason pika leptin induced weight loss, we weighed the organs of mice exposed to different temperature conditions. 18.2 6 3.3 cm in PBS-controls (not significant, NS). Body length in leptin-treated mice measured 18.5 6 2.3 cm vs. CP: 4.12 g/day, p, 0.05) and consequently body weight as well (reduction of body weight over 7 days, CL: 0.33 g vs. Under cold exposure pika leptin also significantly reduced food intake in CL mice (cold exposed mice receiving leptin treatment) compared to CP mice (cold exposed mice receiving PBS buffer) (CL: 3.48 g/ day vs. Prolonged cold exposure (5 6 1 u C) had obvious effects on energy homeostasis as observed by increased food intake by CP mice (cold exposed mice receiving PBS buffer) compared to WP mice (warm exposed mice receiving PBS buffer) (WP: 3.60 g/day vs.

Plateau pika