The purpose of this study was to determine the effect of DHEA on Type Ⅰ(soleus) and Ⅱ muscles(plantaris, gastronemius) in a focal brain ischemia model rat.
Thirty-seven male Sprague-Dawley rats with 200~250g body weights were randomly divided into four groups : CINS(cerebral ischemia + normal saline), CIDH(cerebral ischemia + DHEA), SHNS(sham + normal saline), SHDH (sham + DHEA). Both the CINS and CIDH
groups were undergone a transient right middle cerebral artery occlusion operation. In the SHNS and SHDH groups, a sham operation was done. DHEA was administered daily at a dose of 0.34m㏖/㎏, and normal saline was administered daily at the same dose by
intraperitoneal injection for 7days after operation. Cerebral infarction in the CINS and CIDH groups was identified by staining with 2% triphenyltetrazolium chloride solution for 60 minutes. The data were analyzed by Kruskal-Wallis test and Mann-Whitney
U test using the SPSSWIN 9.0 program.
The results were summarized as follows:
1) The muscle weights of soleus(Type Ⅰ), plantaris and gastrocnemius(Type Ⅱ) in CINS group were significantly less than those of the SHNS group(p<.01). The muscle fiber cross-sectional area of the CINS group was significantly less than that of the
SHNS group in Type Ⅰ muscle fiber of the soleus and Type Ⅱ muscle fiber of the plantaris and gastrocnemius(p<.05). The myofibrillar protein content of the CINS group was significantly less than that of the SHNS group in the left gastrocnemius and
right soleus(p<.05).
2) The muscle weights of the soleus, plantaris and gastrocnemius except the unaffected side of the plantaris in the CIDH significantly increased compared to those of the CINS group(p<.05). The muscle fiber cross-sectional area of the CIDH group
significantly increased compared to that of the CINS group in Type Ⅱ muscle fiber of the plantaris and gastrocnemius(p<.05). The myofibrillar protein content of the CIDH group significantly increased compared to that of the CINS group in the left
soleus(p<.05).
3) On the post-op 8 day, the body weight of the CINS group was significantly less than that of the CIDH, SHNS and SHDH groups(p<.01). Total diet intake of the CINS and CIDH groups was significantly less than that of the SHNS and SHDH
groups(p<.01).
Based on these results, it was identified that muscle atrophy could be induced during the 7 days after cerebral infarction, and DHEA administration during the early stage of cerebral infarction might attenuate muscle atrophy.
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