@article{oai:ir.kagoshima-u.ac.jp:00001225, author = {北野, 元生 and Kitano, Motoo and 吉田, 愛知 and Yoshida, Aichi and 服部, 正策 and Hattori, Shosaku and 大野, 素徳 and Ono, Motonori}, journal = {鹿児島大学歯学部紀要}, month = {Mar}, note = {The lesions caused by sublethal doses of Trimeresurus flavoviridis (Tf) venom injected into the anterior thigh muscle (quadriceps femoris muscle; QFM) of rats were studied using paraffin sections. A dose of 50 f*g of Tf venom produced a large area of necrosis in the QFM together with the neighboring muscles. Phagocytosis of necrotic remnants was followed by marked regeneration of muscle fibers. Myonecrosis was microscopically evident 30 minutes after injection, and over the following 72 hours the necrotic muscles remained acellular and were devoid of inflammatory reaction, except at the very edge where liquefaction necrosis associated with inflammatory infiltrate was marked from the beginning. Blood vessels within and outside the necrotic foci were occasionally involved in collapse and/or in inflammatory changes with thrombosis, to some degree. However, marked hemorrhage was never noted in and around the foci. Phagocytosis of debris proceeded from the periphery, and after 24 hours the muscle was replaced by granulation tissue containing many regenerating myoblastic cells. Abscesses developed in the vicinity of the injection site in several rats receiving Tf venom but never after injection of its phospholipase A2 isozymes, PLA2, BPI, or BPII. Muscle necrosis after envenomation of Tf venom seems to be due primarily to direct action of the venom, although vascular thrombosis and ischemia may also contribute. Interestingly, in rats, myonecrotic Tf venom itself may cause marked and extensive activation of muscle fiber regeneration. The venom seems to be a strong myotoxin but not a hemorrhagenic toxin. Tf serum proteins were fractionated by ammonium sulfate precipitation to six portions depending on its degree of saturability, 0-20%, 20-30%, 30-40%, 40-50%, and 50-70%. The effects of these proteins on Tf venom-induced rat skeletal muscle damage were investigated with closer attention to histopathological features of impairment, necrosis, and regeneration of muscle fibers. The results indicated that the rats injected with Tf crude venom together with the serum protein fraction of ammonium sulfate saturation 40-50% showed necrotic changes were smallest of all in the rats treated together with the other serum protein fractions. The knowledge that Tf serum proteins are effective in preventing local lesions caused by Tf venom should shed light on effective medical treatment following Tf snake bites.}, pages = {15--24}, title = {Prevention of Muscle Necrosis Induced in Rats after Envenomation of Trimeresurus flavoviridis (Amami-Oshima Island) Venom and Its Components, Phospholipase A_2 Isozymes}, volume = {23}, year = {2003} }