The Kallikrein-kinin System in Non-tetrapod Vertebrates

9418819哺乳动物(包括人类)中的特定酶(激肽释放酶)裂解循环蛋白(激肽原)，产生一种小肽(缓激肽)，参与调节血液流动以及神经元和平滑肌活动。这一过程被称为激肽释放酶-激动素系统，但目前尚不清楚该系统在进化过程中何时出现，或者它是否在非哺乳动物脊椎动物中发挥重要的功能作用。Conlon博士建议在不同进化水平上检查各种水生脊椎动物的血浆样本，以确定该系统组件的存在。他已经从鲑鱼和具有系统发育的古老鱼类弓鳍中提纯了与缓激肽相关的新型多肽，并建议系统地研究这些多肽在其起源物种中的生物活性。康伦博士将使用慢性插管动物研究对心血管参数的影响，并使用分离的组织制剂确定多肽的目标位置。这些数据将使人们能够评估激肽释放酶-激肽系统在鱼类中的生理重要性。***

9418819 Conlon In mammals, including the human, specific enzymes (kallikreins) cleave a circulating protein (kininogen) to generate a small peptide (bradykinin) that is involved in regulating blood flow and both neuronal and smooth muscle activity. This process is referred to as the kallikrein-kinin system but it is not known when the system arose in evolution or whether it plays an important functional role in non-mammalian vertebrates. Dr. Conlon proposes to examine plasma samples from a wide range of aquatic vertebrates at different levels of evolution for the presence of the components of the system. He has already purified novel bradykinin-related peptides from the trout and from the phylogentically ancient fish, the bowfin, and he proposes to systematically investigate the biological activities of the peptides in their species of origin. Dr. Conlon will study effects on cardiovascular parameters using chronically cannulated animals and identify target sites for the peptides using isolated tissue preparations. The data will permit an assessment of the physiological importance of the kallikrein-kinin system in fish. ***