A rat model for acute limb ischemia using microsized gelatin beads.

OBJECTIVE: Acute limb ischemia (ALI) is a rapid decrease in lower limb blood flow due to acute occlusion of peripheral arteries or bypass grafts. This study aimed to establish an ALI model using microsized gelatin beads and to investigate the pathophysiological conditions. METHODS: Male Sprague-Dawley rats were anesthetized, and a low or high dose of microsized gelatin beads was administered into the left femoral artery on days 0 and 7. A control, that is, normal saline (NS) group in which NS was administered in the left femoral artery, a femoral artery cut (FAC) group in which the left femoral artery was cut, and a sciatic nerve cut (SNC) group in which the left sciatic nerve was cut were prepared. After 21 days, the temperature changes and the muscle weights in the lower limbs were measured. To assess nerve damage, the L1-6 sympathetic ganglia were immunostained with activating transcription factor 3 (ATF3) antibody. RESULTS: In the Low-dose, High-dose, and FAC groups, a decrease in temperature was predominantly observed in the left limb. In the High-dose and SNC groups, the weight of the soleus muscle and extensor digitorum longus in the left limb decreased; however, no weight changes were observed in the Low-dose and FAC groups. Conversely, the weight of the gastrocnemius muscle significantly decreased in the Low-dose, High-dose, FAC, and SNC groups. In the High-dose and SNC groups, the number of ATF3-positive cells in the sympathetic ganglia significantly increased, and in the Low-dose, a small number of ATF3-positive cells were observed. However, ATF3-positive cells were rarely observed in the FAC and NS groups. CONCLUSION: We established an ALI rat model using microsized gelatin beads. The results of this study suggest that autonomic neuropathy in ALI is related to both muscle damage and peripheral neuropathy.

[Ultrastructural changes of collagen fibrils in mouse dermal connective tissue after moxibustion treatment].

Morphological changes in mouse back skin, especially dermal connective tissue, were observed after moxibustion treatment. Various amounts of direct moxibustion and indirect moxibustion (column) were performed and the exact skin area was processed for light and electron microscopy. Just after treatment, epidermal cell layer was degenerated and increased amounts of mast cells were observed. Many unwinding collagen fibrils were prominent. Twenty-four hours after treatment, the number of unwinding fibrils decreased. Instead, tightly winding fibrils, sometimes thicker, were observed in a similar area. D-period of collagen fibrils did not change in any situation. Physical reaction to moxibustion varies depending on stimulation rate and/or approach, which includes the change of interstitial connective tissues as well as cellular profiles. It is also important to survey the time-dependent changes in moxibustion treatment.