Studies on the electrolyte transport in corneal cells.

角膜细胞电解质转运的研究。

• 批准号: 03044087
• 负责人: HONDA Yoshihito
• 金额: $ 2.43万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03044087/
• 关键词: Corneal endothelial cells; corneal epithelial cells; endothelin; cytosolic Ca2+ concentration; PI turnover; mitognesis; 細胞内カルシウム; 家兎; サイクリックAMP

The transparency of the cornea is very important for the maintenance of good visual function. Normal functional state of corneal epithelial cells as well as endothelial cells are important for the corneal transparency. In this study we have investigated endothelin-induced mitogenesis and the second messenger systems working in cultured rabbit corneal epithelial cells.We have clearly demonstrated the following :1) Cultured rabbit corneal endothelial cells produce endothelin. The occurrence of mRNA for prepro-endothelin was found by reverse transcription initiated polymerase chain reaction. In the culture supernatant of the rabbit corneal epithelial cells, radioreactive endothelin was found.2) Endothelin dose-dependently increases mitogenesis of cultured rabbit corneal epithelial cells. Endothelin 1 dose-dependently increased (EC50 = 0.3 nM) 3H-thymidine uptake of the cell up to 200% of the control. Endothelin was shown to be a comitogen because coexistence of low concentration of fetal bovine serum increased the mitogenic effect.3) Endothelin increases intracellular cytosolic Ca^<2+> concentration in the cell. Endothelin, at 100 nM, increased cytosolic free Ca^<2+> concentration by more than 200 nM. This phenomenon was preceded by PI turnover.

角膜的透明度对于维持良好的视觉功能非常重要。角膜上皮细胞和内皮细胞的正常功能状态对角膜的透明性至关重要。本实验研究了内皮素诱导的兔角膜上皮细胞有丝分裂和第二信使系统的作用，结果表明：1）培养的兔角膜内皮细胞产生内皮素。逆转录聚合酶链反应检测内皮素前原mRNA的表达。在培养的兔角膜上皮细胞培养上清中，发现放射活性内皮素。2）内皮素剂量依赖性地促进培养的兔角膜上皮细胞的有丝分裂。内皮素1剂量依赖性增加（EC 50 = 0.3 nM）3 H-胸苷摄取的细胞高达200%的控制。低浓度胎牛血清的共存可增强内皮素的促有丝分裂作用，内皮素可作为促有丝分裂剂; 3）内皮素可增加细胞内Ca^2+浓度。内皮素在100 nM时可使胞浆游离Ca^2+浓度增加200 nM以上。这一现象之前PI营业额。

项目成果

Hitoshi Takagi: "Endothelin-induced cytosolic Calcium transients in Cultured rabbit corneal epithelial cells." Investigative Ophthalmology and Visual Science. 33. 1199 (1992)

Hitoshi Takagi：“培养的兔角膜上皮细胞中内皮素诱导的胞质钙瞬变。”

Peter.S.Reinach: "Autocrine Mediated Stimulation of Mitosis by Edothelin(ET) in cultured Rabbit corneal" Investigative Ophthalmology and Visual Science. 34. (1993)

Peter.S.Reinach：“培养兔角膜中埃多皮素 (ET) 自分泌介导的有丝分裂刺激”眼科和视觉科学研究。

Takagi,T,Reinach,PS,and Yoshimura,N: "Endothelin-inducid Cytosolic Calcium Transients in Cultured Rabbit Corneal Epithelial Cells." Invest Ophthalmol Vis Sci. 33. (1992)

Takagi,T、Reinach,PS 和 Yoshimura,N：“培养的兔角膜上皮细胞中内皮素诱导的细胞溶质钙瞬变。”

Hitoshi TAKAGI,: "Endothelin-indvced cytosolic calcivm Transients in cultured rabbit corneal epithelial cells." Investigative Ophthalmology and Visual Science. 33. (SUPPL)1199 (1992)

Hitoshi TAKAGI，：“培养的兔角膜上皮细胞中内皮素诱导的胞浆钙瞬变。”

Peter. S. Reinach: "Autocrine mediated stimulation of mitosis by Endothelin(ET) in Cultured Rabbit corneal Epithelial cells." Investigative Ophthalmology and Visual Science. 34. (1993)

彼得.