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蛙皮素可调节机体内环境恒定 14肽蛙皮素(bombesin)最初是从青蛙的皮肤中分离,晚近的研究发现,它也存在于哺乳动物的胃肠道和脑内。其后,又相继发现了C-末端10个氨基酸基本相同的27肽蛙皮素和约为32肽的蛙皮素。放射免疫测定表明,大鼠脑内蛙皮素含量最高的部位是下丘脑,这正是植物性神经最重要的整合中枢。大鼠侧脑室注射蛙皮素可引起体温明显改变,但该效应随动物所处环境温度的不同而异。环境温度为4～24℃时有明显降温作用。定位研究提示其作用部位似乎在下丘脑前部视前区。这种作用不是通过乙酰胆碱、多巴胺、去甲肾上腺素、GABA等传递;但可被促甲状腺激素释放激素、生长抑素和纳络酮对抗。在低温环境中蛙皮素的降温作用主要与散热增加、促甲状腺激素分泌减少和耗氧量减少有关。
Bombesin regulates the body’s environment 14 bombesin was initially isolated from the skin of frogs and recent research has found that it is also present in the gastrointestinal tract and brain of mammals. Since then, 27 cephalosporins and about 32 peptides have been found in the C-terminal ten amino acids. Radioimmunoassay showed that the highest content of bombesin in the rat brain is the hypothalamus, which is the most important integration center of autonomic nerve. Injection of bombesin into the lateral ventricle can cause significant changes in body temperature, but the effect varies with the ambient temperature at which the animal is exposed. Ambient temperature is 4 ~ 24 ℃ significant cooling effect. Positioning studies suggest that the site of its role in the hypothalamus seems preoptic area. This effect is not transmitted by acetylcholine, dopamine, norepinephrine, GABA, etc .; but can be thyrotropin-releasing hormone, somatostatin and naloxone confrontation. In low temperature environment, the role of Bombesin cooling mainly associated with increased heat, reduced thyroid stimulating hormone secretion and decreased oxygen consumption.