PITUITARY KININOGENASES--PROPERTIES AND REGULATION

建议的研究目的是研究生物化学。 特性、亚细胞分布和生理调节 激动型蛋白水解酶(激肽原酶)的意义 在大鼠和猪的脑下垂体中检测到。大鼠和猪脑垂体腺 激肽原酶将被溶解，并使用组合 亲和层析和凝胶过滤层析。纯化的激肽原酶将是 具有相对分子质量、专一性和动力学的特征 底物水解，对合成和天然抑制剂的敏感性，以及 将完整的大鼠前阿片黑素皮质素分解到其激素中的能力 从ACTH中片段并产生阿片或黑素细胞刺激肽 或者是β-促脂激素。大鼠和猪的脑下垂体将被匀浆 蔗糖缓冲液和各种亚细胞级分 差速离心法与不连续蔗糖的组合 密度梯度；不同亚细胞中的激肽原酶活性 将使用合成和天然底物来确定组分 激肽原酶。在大鼠中，垂体激肽原酶对不同种类的 内分泌和药物操作将在体外进行检查。 在体内，为了表征可能调节的因素 脑下垂体激肽原酶及其功能。此外，脑下垂体 各种老鼠品系、两栖动物和爬行动物将与 对激肽原酶活性的影响。拟议的研究应该澄清 不同类型垂体激肽原酶的特性 不同物种的脑叶，并提示激肽原酶可能如何调节 脑下垂体功能。这样的研究应该为未来奠定基础 激肽原等蛋白水解酶在垂体中的作用研究 利用药理学、内分泌学和分子生物学技术发挥功能 生物学。脑下垂体有望成为研究如何 特定的蛋白水解酶调节分泌物的转运后处理 蛋白质。这样的研究可能最终会阐明 临床综合征中的蛋白水解酶，其特征是产物改变 多肽激素或其他蛋白质产品。

The objective of the proposed research is to study the biochemical properties, subcellular distribution, and physiological regulation and significance of kiningenerating proteinases (kininogenases) I have recently detected in rat and porcine pituitaries. Rat and porcine pituitary kininogenases will be solubilized, and purified using a combination of affinity and gel-filtration chromatography. Purified kininogenases will be characterized with regard to molecular weight, specificity and kinetics of substrate hydrolysis, sensitivity to synthetic and natural inhibitors, and ability to cleave intact rat pro-opiomelanocortin into its hormonal fragments and generate opioid or melanocyte-stimulating peptides from ACTH or Beta-lipotropin. Rat and porcine pituitaries will be homogenized in sucrose buffer and various subcellular fractions prepared using a combination of differential centrifugation and discontinuous sucrose density gradients; kininogenase activity in the various subcellular fractions will be determined using synthetic and natural substrates for kininogenases. In the rat, responses of pituitary kininogenases to various endocrine and pharmacological manipulations will be examined both in vitro and in vivo in order to characterize the factors which may regulate pituitary kininogenases and their function. In addition, pituitaries of various mouse strains, amphibians, and reptiles will be compared with respect to kininogenase activity. The proposed research should elucidate the characteristics of kininogenases associated with various pituitary lobes in different species and suggest how kininogenases may regulate pituitary function. Such studies should lay the foundation for future research on the role of kininogenses and other proteases in pituitary function using techniques of pharmacology, endocrinology, and molecular biology. The pituitary promises to be a model system for studying how specific proteases regulate the post-tranalational processing of secretory proteins. Such research may ultimately illuminate the involvement of proteases in clinical syndromes characterized by an altered production of peptide hormones or othe protein products.