THE DEVELOPMENT OF LASER-FLUOROMETRIC MICROSCOPE FOR MEASUREMENT OF INTRACELLULAR CALCIUM IONS SINGLE LIVING CELLS.

利用紫外激光和Indo-1技术，建立了一套准确灵敏的血管平滑肌细胞（VSMC）细胞质游离钙浓度（[Ca^<++>]_i）测量系统。自发性高血压大鼠（SHR） [Ca^<++>]_i在第6代培养后升高并维持。此外，在一些4周龄SHR人群中，即使血压和基础[Ca^<++>]_i尚未升高，咖啡因和血管紧张素- ii刺激后的VSMC [Ca^<++>]_i也明显升高。与Wistar Kyoto大鼠相比，8周龄大鼠SHR的基础[Ca^<++>]_i升高。我们试图从SHR血清中鉴定出在VSMC中升高[Ca^<++>]_i的尚未确定的循环因子。结果表明：1)SHR患者VSMC中[Ca^<++>]_i水平的维持是受基因调控的，这是SHR高血压的机制之一；2)SHR引起的VSMC中钙的异常调节甚至在明显的高血压之前表达；3)8W-SHR血清中存在[Ca^<++>]_i升高因子，但在4W-SHR、4W-和8W- WKY血清中不存在。

We have developed an accurate and sensitive system for the measurement of cytoplasmic free calcium concentrations ([Ca^<++>]_i) of a single vascular smooth muscle cell (VSMC) by using UV-laser and Indo-1. [Ca^<++>]_i in spontaneously hypertensive rat (SHR) was elevated and maintained after the 6th passage culture. And moreover, marked elevation of [Ca^<++>]_i after stimulation with caffeine and angiotensin-II occurred in VSMC in some populations of 4-week-old SHR even when blood pressure and basal [Ca^<++>]_i had not yet been elevated. In 8-week-old rats, the basal [Ca^<++>]_i from SHR was elevated compared with Wistar Kyoto rats. We have attempted to characterize yet unspecified circulating factor(s) from SHR serum that elevates [Ca^<++>]_i in VSMC. Our results showed that 1) the maintenance of high [Ca^<++>]_i levels in VSMC in SHR is genetically regulated and it is one of the mechanisms in SHR hypertension, 2) abnormal calcium regulation in VSMC from SHR is expressed even prior to overt hypertension, and 3) the [Ca^<++>]_i elevating factor(s) exists in 8W-SHR serum, but not in 4W-SHR, 4W- or 8W- WKY serum.