TY - JOUR
T1 - Effect of serotonin and tricyclic antidepressants on intracellular calcium concentrations in Spisula oocytes
AU - Juneja, R.
AU - Ito, E.
AU - Koide, S. S.
PY - 1994/1
Y1 - 1994/1
N2 - Microspectrofluorometry and video imaging techniques were used to study and to compare the changes in intracellular calcium concentrations ([Ca2+]i) of individual Fura-2 loaded Spisula oocytes treated with serotonin (5-hydroxytryptamine, 5-HT) or tricyclic antidepressants. In the present study, we showed that 5-HT increased [Ca2+]i in freshly isolated Spisula oocytes suspended in artificial sea water. In the absence of extracellular Ca2+, 5-HT did not influence [Ca2+]i. Stimulation of [Ca2+]i by 5-HT was blocked by calcium channel blocker, e.g. verapamil, and by tricyclic antidepressants. These observations combined with our previous results on the effects of 5-HT, tricyclic antidepressants and verapamil on calcium uptake suggest that the increase in [Ca2+]i induced by 5-HT results from an influx of extracellular calcium through calcium channels, which can be blocked by tricyclic antidepressants. The use of the Fura-2 imaging technique allowed single-cell measurements and defined changes induced by 5-HT in [Ca2+]i which is the net result of calcium uptake and release of intracellular calcium from storage sites in individual Spisula oocytes.
AB - Microspectrofluorometry and video imaging techniques were used to study and to compare the changes in intracellular calcium concentrations ([Ca2+]i) of individual Fura-2 loaded Spisula oocytes treated with serotonin (5-hydroxytryptamine, 5-HT) or tricyclic antidepressants. In the present study, we showed that 5-HT increased [Ca2+]i in freshly isolated Spisula oocytes suspended in artificial sea water. In the absence of extracellular Ca2+, 5-HT did not influence [Ca2+]i. Stimulation of [Ca2+]i by 5-HT was blocked by calcium channel blocker, e.g. verapamil, and by tricyclic antidepressants. These observations combined with our previous results on the effects of 5-HT, tricyclic antidepressants and verapamil on calcium uptake suggest that the increase in [Ca2+]i induced by 5-HT results from an influx of extracellular calcium through calcium channels, which can be blocked by tricyclic antidepressants. The use of the Fura-2 imaging technique allowed single-cell measurements and defined changes induced by 5-HT in [Ca2+]i which is the net result of calcium uptake and release of intracellular calcium from storage sites in individual Spisula oocytes.
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U2 - 10.1016/0143-4160(94)90099-X
DO - 10.1016/0143-4160(94)90099-X
M3 - Article
C2 - 8149402
AN - SCOPUS:0027957638
SN - 0143-4160
VL - 15
SP - 1
EP - 6
JO - Cell Calcium
JF - Cell Calcium
IS - 1
ER -