ALLOXAN RESISTANCE & ISLET REGENERATION IN GUINEA PIG

四氧嘧啶耐药性

• 批准号: 3462878
• 负责人: KENNETH C GORRAY
• 金额: $ 12.5万
• 依托单位: LONG ISLAND JEWISH MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-05-01 至 1994-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3462878
• 关键词: alloxan; autoradiography; drug adverse effect; drug related diabetes mellitus; drug resistance; glucose transport; guinea pigs; histochemistry /cytochemistry; hormone regulation /control mechanism; immunocytochemistry; insulin; laboratory mouse; laboratory rat; pancreatic islets; radiotracer; regeneration; tissue /cell culture

The guinea pig is unique in its physiologic and pancreatic morphological responses to high doses of diabetogen alloxan. Pancreatic B cells of alloxan-treated guinea pigs degenerate, with large numbers of islet cells demonstrating pyknotic nuclei, loss of over 50% of immunostainable B cells, and a marked reduction in serum insulin levels. This is followed, within 72 hrs, by reappearance of a full complement of immunohistochemically staining B cells, and, within 14 days, by restoration of normal serum in- sulin levels. The proposed research will explore the mechanism of B cell regeneration in the alloxan-treated guinea pig. 3H- thymidine labeling combined with immunohistochemistry will be employed to determine: A) whether the regenerated B cells arise mitotically; B) the nature of the progenitors of B cells; C) conditions (including age) which modulate the B cell regeneration. Since we have previously demonstrated that guinea pig B cells do not regenerate following alloxan treatment in vitro, we will also attempt to identify serum and pancreatic factors which can stimulate B-cell regeneration following alloxan-induced B-cell loss in cultures of guinea pig islet cells. Monoclonal antibodies will be raised to cell surface antigens of islets isolated from alloxan- treated regenerating guinea pig pancreas to determine if there is a unique cell population which serves as the source of the regenerated cells, and whether such cells are present in normal and diabetic human pancreas. Alloxan toxicity is due at least in part to free radical damage to B cells. Since guinea pig B cells are relatively resistant to low doses of alloxan, we will use in vitro techniques to determine whether they are resistant to free radical damage via elevated superoxide dismutase levels. Studies of B-cell regeneration and replication of B cells are of great importance to diabetes research. The cultured islet cell system provides both a useful model for the understanding of B-cell differentiation and regeneration following injury, and a sensitive in vitro bioassay for humoral and/or paracrine factors which may stimulate such processes.

豚鼠在生理和胰腺方面是独一无二的 高剂量糖尿病原四氧嘧啶的形态反应。 经四氧嘧啶治疗的豚鼠胰腺B细胞变性， 大量胰岛细胞核固缩、缺失 超过50%的免疫染色B细胞，并显著减少 血清胰岛素水平。这之后，在72小时内， 全套免疫组织化学染色的重现 B细胞，并在14天内恢复正常血清- 苏林水平。这项拟议的研究将探索 四氧嘧啶对豚鼠B细胞再生的影响。3H- 胸腺嘧啶核苷标记结合免疫组织化学将 用于确定：A)再生的B细胞是否产生 有丝分裂；B)B细胞祖细胞的性质；C) 调节B细胞再生的条件(包括年龄)。 因为我们之前已经证明了豚鼠B细胞 在体外四氧嘧啶治疗后不能再生，我们还将 尝试确定血清和胰腺因子可以 四氧嘧啶诱导B细胞丢失后刺激B细胞再生 在豚鼠胰岛细胞培养中。单抗将会 从四氧嘧啶中分离的胰岛的细胞表面抗原- 治疗再生的豚鼠胰腺以确定是否有 一种独特的细胞群体，它是 再生细胞，以及这些细胞是否存在于正常和 糖尿病人的胰腺。四氧嘧啶中毒至少是部分原因 对B细胞的自由基损伤。由于豚鼠B细胞 对低剂量的四氧嘧啶相对耐药，我们将在体外使用 确定它们是否对自由基具有抵抗力的技术 通过超氧化物歧化酶水平升高造成的损害。B细胞的研究 B细胞的再生和复制是非常重要的 糖尿病研究。培养的胰岛细胞系统既提供了 一个有用的模型来理解B细胞的分化和 损伤后的再生和一种灵敏的体外生物测定 体液和/或旁分泌因素可能刺激 流程。