The purpose of this study was to determine the effect of regular exercise during dexamethasone injection on the body weight, weight of hindlimb muscles and adrenal gland in young rats. 80-100g Wistar rats were divided into control, exercise, dexamethasone injection(dexa), and exercise during dexamethasone injection(D+E) group. The dexa group received daily subcutaneous injection of dexamethasone at a dose of 5mg/kg body weight for 10 days. The exercise group ran on a treadmill for 60min/ day(20 minutes every 4 hour at 10m/ min and a 10degrees grade. The control group received daily subcutaneous injection of normal saline at a dose of 5mg/kg body weight for 10 days. The D+E group ran on a treadmill for 60min/day(20 minutes every 4hour) at 10m/min and a 10degrees grade. Body weight of both control and exercise group increased significantly until 10 days, the of both dexa and D+E group decreased significantly, resulting in 79.47 and 78.75% decrease respectively compared to the first day of experiment. Body weight and muscle weight of the soleus, plantaris and gastrocnemius decreased significantly with dexamethasone injection. Relative weight of the dexa group decreased significantly compared to that of the control group. Body weight and muscle weight of the soleus and plantaris of the D+E group showed a tendency to increase, and muscle weight of the gastrocnemius increased significantly compared to the dexa group. The Relative weight of the plantaris was comparable to the control group and that of the soleus and gastrocnemius tended to increase, in the exercise group. Body weight and muscle weight of the soleus and plantaris of the D+E group showed a tendency to increase, and muscle weight of the gastrocnemius increased significantly compared to the dexa group, The Relative weight of the soleus and gastrocnemius tended to increased and that of the plantaris of the D+E group increased significantly compared to the dexa group. Body weight, muscle weight and relative weight of the soleus, plantaris and gastrocnemius of the D+E group increased significantly compared to the dexa group Adrenal gland weight of the dexa and D+E group tended to increase, and that of the exercise group increased significantly. From these results. it can be suggested that regular exercise during dexamethasone injection might attenuate the decrease of body weight and hindllimb muscle weight induced by the dexamethasone injection.

PURPOSE: This study was to determine the effect of DHEA administration before, during, and after dexamethasone treatment on body weight and TypeI,II muscle weight of rat receiving dexamethasone treatment. METHOD: Wistar rats were divided into 6 groups: control(C), dexamethasone(D), DHEA administration for 3days after dexamethasone treatment for 7days(7D+3DH), dexamethasone treatment for 7days after DHEA administration for 3days(3DH+7D), DHEA administration during dexamethasone treatment for 4days after dexamethasone treatment for 3days(3D+4DDH), DHEA administration during dexamethasone treatment for 7days(7DDH). Dexamethasone was injected by subcutaneously daily at a dose of 5mg/kg. DHEA was orally administered daily at a dose of 5mg/kg for 7 days. Soleus(TypeI) muscle, and both plantaris and gastro- cnemius(TypeII) muscles were dissected on the 7th day of experiment. RESULT: Body weight of both 3DH+7D group and 3D+4DDH group increased significantly compared with that of 7D group. Body weight of 7D+3DH group decreased significantly compared with that of 7D group, 7DDH group, 3DH+7D group and 3D+4DDH group. Muscle weight of both plantaris and gastro- cnemius tended to decrease compared with that of 7D group. Muscle weight of 7DDH group, 3D+4DDH group and 3DH+7D group increased significantly compared with that of 7D+3DH group. Muscle weight of gastrocnemius of both 3DH+7D group and 3D+4DDH group increased significantly compared with that of 7D group. CONCLUSION: Based on these results, it can be suggested that DHEA administration before and during dexamethasone treatment can increase both body weight and mass of atrophied TypeII muscle induced by dexa- methasone treatment.

The purpose of this study was to determine the effect of regular exercise during dexamethasone injection in the body weight, weight of hind-limb muscles, myofibrillar protein content and glutamine synthetase activity. 180-200g female Wistar were divided into four groups: control, exercise, dexamethasone injection(dexa), and exercise during dexamethasone injection(D+E) group. The dexa group received daily subcutaneous injection of dexamethasone at a dose of 4mg/kg body weight for 7days. The exercise group ran on a treadmill for 60min/day(20minutes every 4 hours) at 10m/min and a 10degrees grade. The control group received daily subcutaneous injection of normal saline at a dose of 4mg/kg body weight for 7 days. The D+E group ran on a treadmill for 60min/day(20minutes every 4 hours) at 10m/min and a 10degrees grade during dexamethasone injection. Body weight of the control group increased significantly from days of experiment, that of the dexa group decreased significantly from day 4 of the dexa group decrease significantly from day 4 of the experiment resulting in a 82.4% decrease compared to the first day of the experiment. Body weight of the D+E group decrease significantly from day 5 of experiment resulting in a 81.77% decrease compared to the first day of the experiment. Body weights, muscle weight and myofibrillar protein content of the plantaris and gastrocnemius decrease significantly and muscle weight of the sleys tended to decrease with dexamethasone injection. Glutamine synthetase activity of the hind-limb muscles increase significantly with the dexamethasone injection. The relative weight of the soleus was comparable to the control group and that of plantaris decrease significantly and that of gastrocnemius tended to decrease compared to that of the control in the dexa group. Body weight and muscle weight of the plantaris and gastronemius of the exercise group were comparable to the control group, and the muscle weight of soleus showed a tendency to increase. The relative weight of the soleus increased significantly and that of the plantaris and gastrocnemius were comparable to the control in the exercise group. Myofibrillar protein content of the soleus and plantaris increased significantly and there was no change of GS activity of the hind-limb muscles compared to the control in the exercise group. Body weight of the D+E group was comparable to the dexa group, muscle weight of the hind-limb muscles increased significantly. Myofibrillar protein content of the soleus and plantaris increase significantly and that of the gastrocnemius tendency to increase compared to the dexa group. Body weight and muscle weight of the plantaris and gastrocnemius of the D+E group did not recover to that of the control group. Muscle weight of the soleus recovered to that of the control group. The relative weight and myofibrillar protein content of the hind-limb muscles recovered to that of the control group. From these results, it is suggested that regular exercise during dexamethasone injection might attenuate the muscle atrophy of the hind-limb muscles.