Effects of hyperin on free intracellular calcium in dissociated neonatal rat brain cells

目的：研究金丝桃苷（Ｈｙｐ）对新生大鼠的脑细胞内游离钙浓度的作用．方法：分离新生大鼠的脑细胞；用钙离子荧光指示剂Ｆｕｒａ２测定静息和激动剂存在时新生鼠脑细胞内游离钙浓度．结果：在ＣａＣｌ２１３ｍｍｏｌ·Ｌ－１的Ｈａｎｋｓ液中，静息［Ｃａ２＋］ｉ为（２０８±１２）ｎｍｏｌ·Ｌ－１（ｎ＝１７），Ｈｙｐ对静息［Ｃａ２＋］ｉ无明显影响；Ｈｙｐ１０，４０，１６０μｍｏｌ·Ｌ－１呈浓度依赖性显著抑制ＫＣｌ５０ｍｍｏｌ·Ｌ－１致［Ｃａ２＋］ｉ增高；Ｈｙｐ１６０μｍｏｌ·Ｌ－１显著抑制去甲肾上腺素１，２，４和８μｍｏｌ·Ｌ－１诱发的［Ｃａ２＋］ｉ的增高；Ｈｙｐ１６０μｍｏｌ·Ｌ－１还可显著抑制谷氨酸和５羟色胺致［Ｃａ２＋］ｉ增高．结论：Ｈｙｐ对新生大鼠脑细胞钙内流有阻滞作用．

AIM: To study the effects of hyperin (Hyp) on free intracellular calcium concentration ([Ca 2+ ] i) of brain cells. METHODS: The neonatal rat brain cells were dissociated. [Ca 2+ ] i in presence and absence of extracellular high K +, L glutamic acid (Glu), 5 hydroxy￣tryptamine (5 HT), and norepinephrine (NE) were assayed with Fura 2 AM. RESULTS: The resting [Ca 2+ ] i in Hanks solution (CaCl 2 1 3 mmol·L -1 ) was (208±12) nmol·L -1 ( n =17). Hyp had no significant effects on the resting [Ca 2+ ] i. Hyp 1 0, 4 0, and 16 0 μmol·L -1 markedly inhibited the increase of [Ca 2+ ] i evoked by K + 50 mmol·L -1 in a concentration dependent manner. Hyp 16 0 μmol·L -1 inhibited the increases of [Ca 2+ ] i induced by NE 1, 2, 4, and 8 μmol·L -1 . Hyp (16 0 μmol·L -1 ) also markedly attenuated 5 HT and Glu induced increase of [Ca 2+ ] i. CONCLUSION: Hyp possessed inhibitory effects on influx of Ca 2+ in the neonatal rat brain cells.