in the previous studies, we found that lumbrokinase an, extract from korean earan earthworm, had a strong in vitro thrombolvtic effect, and that when added to thrombin, bad a significant effect in reducing fatality rate in thrombin-induced lung
infarction mice model. To determine whether it also has in vivo thrombolytic effect in cerebral embolism model, using 0 Spraw Dawly male rats of 200to 300gm, we cannulated the external carotid arteries with poyeth ylene tubes and occluded the
pterygopalatine arteries. Via the external carotid arteries, we in jected 1 mm3 of human blood clots which were previously mixed withTc-99m sulfur colloid.
After confirming the intracranially situated clot by γcamera, we intra-arterially injected 3cc of following flurds to each group of three rats: saline, urokinase of 30,000 units, and lumbrokinase fraction Ⅲ. Then using γcamera of 64×64
matrix,
digital images were obtained for 1 minute in every 30 minutes. After 150 minutes, the average reduction of radioactivities of radioactivities of the clots in the brain were 3.02%, 21.02%, and 24.23% in the saline, urokinase, and lumbrokinase
treated
animals respectively in the liver, the uptake of radioactivites was accordingly increased. Brain sections showed no significant intracranial bleeding in any of the treated animals.
Therefore, we conclude that lumbrokinase has in vivo thrombolytic effects in the rat throm boembolism model without producing significant intracranial bleeding. However, compared with its in vitro effects, the in vivo effects appear to be less
potent.
Further experiments with better designed animal models are warranted.
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