부산대학교 도서관

Suspension hypokinesia is a new model which can simulate some effects of microgravity on the organism of laboratory animals. Two groups of male SPF-bred Wistar rats were suspended for 24 h. In the first group hypokinesia began in the morning (M) (1 h after light onset, 0800 h), whereas the other group was subjected to this treatment from the evening (E) (1 h after dark onset, 2000 h). In the serum, there was a statistically significant increase in non-esterified fatty acids, triacylglycerols (TG) and glucose and a decrease in triiodothyronine concentration in the M group, while only a significant increase in phospholipids (PL) was found in the E group. The serum corticosterone level was increased in both groups, more markedly in the M group. There was an increase in TG and PL in the liver in M rats. In the bone marrow (femur), an increase of triglycerols in E rats and an increase of phospholipids in M rats were found. The concentration of glycogen in the heart muscle, m. quadriceps femoris and m. soleus rose in the M group only. The changes in the analyzed parameters predominate in the rats subjected to hypokinesia in the morning period. This fact confirmed the hypothesis about a higher sensitivity of rats to the stressor acting in the period of inactivity.