Z W Chen1, C G Ma. 1. Department of Pharmacology, Anhui Medical University, Hefei, China. aydxt@public.ah.hf.cn
Abstract
AIM: To study the effects of hyperin (Hyp) on free intracellular calcium concentration ([Ca2+]i) of brain cells. METHODS: The neonatal rat brain cells were dissociated. [Ca2+]i in presence and absence of extracellular high K+, L-glutamic acid (Glu), 5-hydroxytryptamine (5-HT), and norepinephrine (NE) were assayed with Fura 2-AM. RESULTS: The resting [Ca2+]i in Hanks' solution (CaCl2 1.3 mmol.L-1) was (208 +/- 12) nmol.L-1 (n = 17). Hyp had no significant effects on the resting [Ca2+]i. Hyp 1.0, 4.0, and 16.0 mumol.L-1 markedly inhibited the increase of [Ca2+]i evoked by K+ 50 mmol.L-1 in a concentration-dependent manner. Hyp 16.0 mumol.L-1 inhibited the increases of [Ca2+]i induced by NE 1, 2, 4, and 8 mumol.L-1. Hyp (16.0 mumol.L-1) also markedly attenuated 5-HT and Glu-induced increase of [Ca2+]i. CONCLUSION: Hyp possessed inhibitory effects on influx of Ca2+ in the neonatal rat brain cells.
AIM: To study the effects of hyperin (Hyp) on free intracellular calcium concentration ([Ca2+]i) of brain cells. METHODS: The neonatal rat brain cells were dissociated. [Ca2+]i in presence and absence of extracellular high K+, L-glutamic acid (Glu), 5-hydroxytryptamine (5-HT), and norepinephrine (NE) were assayed with Fura 2-AM. RESULTS: The resting [Ca2+]i in Hanks' solution (CaCl2 1.3 mmol.L-1) was (208 +/- 12) nmol.L-1 (n = 17). Hyp had no significant effects on the resting [Ca2+]i. Hyp 1.0, 4.0, and 16.0 mumol.L-1 markedly inhibited the increase of [Ca2+]i evoked by K+ 50 mmol.L-1 in a concentration-dependent manner. Hyp 16.0 mumol.L-1 inhibited the increases of [Ca2+]i induced by NE 1, 2, 4, and 8 mumol.L-1. Hyp (16.0 mumol.L-1) also markedly attenuated 5-HT and Glu-induced increase of [Ca2+]i. CONCLUSION: Hyp possessed inhibitory effects on influx of Ca2+ in the neonatal rat brain cells.