Rajdev S, Reynolds I J
Department of Pharmacology, University of Pittsburgh, PA 15261.
Neurosci Lett. 1993 Nov 12;162(1-2):149-52. doi: 10.1016/0304-3940(93)90582-6.
We describe here the properties of calcium green-5N (CG5N), a novel Ca(2+)-sensitive fluorescent probe. CG5N binds Ca2+ with an affinity of 4.29 +/- 0.67 microM. Ca2+ binding is associated with a 14.7-fold increase in fluorescence. Mg2+ binds to CG5N with an affinity of 5 mM but produces a very small change in fluorescence. Using CG5N [Ca2+]i was recorded in single cultured neurons from fetal rat forebrain. Glutamate together with glycine increased [Ca2+]i by 1.17 +/- 0.15 microM. Pretreating cells with 5 mM potassium cyanide significantly potentiated the response to glutamate, resulting in a mean increase of 8.8 +/- 2 microM. These results demonstrate that CG5N is a useful indicator for measuring very large changes in [Ca2+]i in neurons.
我们在此描述新型Ca(2+)敏感荧光探针钙绿-5N（CG5N）的特性。CG5N与Ca2+结合的亲和力为4.29±0.67微摩尔。Ca2+结合伴随着荧光增强14.7倍。Mg2+与CG5N结合的亲和力为5毫摩尔，但荧光变化非常小。使用CG5N记录了胎鼠前脑单个培养神经元中的[Ca2+]i。谷氨酸与甘氨酸共同作用使[Ca2+]i增加了1.17±0.15微摩尔。用5毫摩尔氰化钾预处理细胞可显著增强对谷氨酸的反应，导致平均增加8.8±2微摩尔。这些结果表明，CG5N是测量神经元中[Ca2+]i非常大变化的有用指标。
