Thymic weight and thymocytes were normal in mice exposed to 2G for 14 days.

(A) Ratio of thymic weight to body weight (left) and total thymic cell number (right) of mice exposed to 2 g gravity (2G) for 14 day or normal gravity control (C). Vestibular apparatus are surgically disrupted in some groups of mice (labeled as VL). N = 6 each C, C with VL, and 2G with VL groups. N = 5 for 2G. NS indicates that the difference is not significant (Student’s t-test). (B) Flow cytometric analysis data of thymocytes in mice exposed to 2G for 14 days. Mice were exposed to 2 g gravity (labeled as 2G) for 14 days or left under 1G (control). Vestibular apparatus are surgically disrupted in some groups of mice (VL). Thymocytes were analyzed by staining with CD4 and CD8α antibodies. Numbers in panels indicate percentage of each fraction. Percentage and numbers of CD4- and CD8-double positive thymocytes (DP) are summarized in right figures. N = 6 each C, C with VL, and 2G with VL groups. N = 5 for 2G. The asterisks indicate statistical significance at *P < 0.05 (Student’s t-test). NS indicates that the difference is not significant (Student’s t-test).