{"title":"5 -羟色胺诱导的动脉平滑肌细胞系细胞内钙变化的时空分辨率。","authors":"W F Goldman","doi":"10.1159/000158870","DOIUrl":null,"url":null,"abstract":"<p><p>Ca2+ transients (1-2 microM) evoked by serotonin (5-HT) in cultured A7r5 cells were studied using fura-2 and digital imaging microscopy. Fura-2 was introduced into cells either by incubation with its acetoxymethyl ester analogue fura-2/AM or by transient ATP-induced permeabilization of the sarcolemma such that the free fura-2 entered the cell directly. The distribution of cytoplasmic Ca2+ in unstimulated cells loaded by the former method was heterogeneous, reflecting, in part, separate pools of Ca2+ in the cytosol and sarcoplasmic reticulum (SR). In contrast, the distribution of Ca2+ was uniform in cells loaded with fura-2 by transient permeabilization; this reflected the restriction of fura-2 to the cytosol. Average Ca2+ in these cells was substantially lower than that in fura-2/AM-loaded cells, because SR Ca2+ influences the fura-2 signal from fura-2/AM-loaded cells, but not from cells loaded with free fura-2. The differences in the Ca2+ distribution measured by the two loading methods were also evident during the course of 5-HT-evoked Ca2+ transients. Spatial and temporal resolution of the rising phase of 5-HT-evoked Ca2+ transients in fura-2/AM-loaded cells revealed that the onset of the Ca2+ transients was first manifested as small regions of elevated Ca2+ that subsequently expanded until peak apparent intracellular Ca2+ levels were present in virtually all of the nonnuclear regions of the cells. The rate of rise of Ca2+ varied in different cell regions with the nucleus responding the slowest.</p>","PeriodicalId":9009,"journal":{"name":"Blood vessels","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"1991-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1159/000158870","citationCount":"10","resultStr":"{\"title\":\"Spatial and temporal resolution of serotonin-induced changes in intracellular calcium in a cultured arterial smooth muscle cell line.\",\"authors\":\"W F Goldman\",\"doi\":\"10.1159/000158870\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Ca2+ transients (1-2 microM) evoked by serotonin (5-HT) in cultured A7r5 cells were studied using fura-2 and digital imaging microscopy. Fura-2 was introduced into cells either by incubation with its acetoxymethyl ester analogue fura-2/AM or by transient ATP-induced permeabilization of the sarcolemma such that the free fura-2 entered the cell directly. The distribution of cytoplasmic Ca2+ in unstimulated cells loaded by the former method was heterogeneous, reflecting, in part, separate pools of Ca2+ in the cytosol and sarcoplasmic reticulum (SR). In contrast, the distribution of Ca2+ was uniform in cells loaded with fura-2 by transient permeabilization; this reflected the restriction of fura-2 to the cytosol. Average Ca2+ in these cells was substantially lower than that in fura-2/AM-loaded cells, because SR Ca2+ influences the fura-2 signal from fura-2/AM-loaded cells, but not from cells loaded with free fura-2. The differences in the Ca2+ distribution measured by the two loading methods were also evident during the course of 5-HT-evoked Ca2+ transients. Spatial and temporal resolution of the rising phase of 5-HT-evoked Ca2+ transients in fura-2/AM-loaded cells revealed that the onset of the Ca2+ transients was first manifested as small regions of elevated Ca2+ that subsequently expanded until peak apparent intracellular Ca2+ levels were present in virtually all of the nonnuclear regions of the cells. The rate of rise of Ca2+ varied in different cell regions with the nucleus responding the slowest.</p>\",\"PeriodicalId\":9009,\"journal\":{\"name\":\"Blood vessels\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"1991-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://sci-hub-pdf.com/10.1159/000158870\",\"citationCount\":\"10\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Blood vessels\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1159/000158870\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Blood vessels","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1159/000158870","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Spatial and temporal resolution of serotonin-induced changes in intracellular calcium in a cultured arterial smooth muscle cell line.
Ca2+ transients (1-2 microM) evoked by serotonin (5-HT) in cultured A7r5 cells were studied using fura-2 and digital imaging microscopy. Fura-2 was introduced into cells either by incubation with its acetoxymethyl ester analogue fura-2/AM or by transient ATP-induced permeabilization of the sarcolemma such that the free fura-2 entered the cell directly. The distribution of cytoplasmic Ca2+ in unstimulated cells loaded by the former method was heterogeneous, reflecting, in part, separate pools of Ca2+ in the cytosol and sarcoplasmic reticulum (SR). In contrast, the distribution of Ca2+ was uniform in cells loaded with fura-2 by transient permeabilization; this reflected the restriction of fura-2 to the cytosol. Average Ca2+ in these cells was substantially lower than that in fura-2/AM-loaded cells, because SR Ca2+ influences the fura-2 signal from fura-2/AM-loaded cells, but not from cells loaded with free fura-2. The differences in the Ca2+ distribution measured by the two loading methods were also evident during the course of 5-HT-evoked Ca2+ transients. Spatial and temporal resolution of the rising phase of 5-HT-evoked Ca2+ transients in fura-2/AM-loaded cells revealed that the onset of the Ca2+ transients was first manifested as small regions of elevated Ca2+ that subsequently expanded until peak apparent intracellular Ca2+ levels were present in virtually all of the nonnuclear regions of the cells. The rate of rise of Ca2+ varied in different cell regions with the nucleus responding the slowest.