Abstract
The inhibition of agonist-stimulated divalent cation inflow in hepatocytes by Gd3+ and compound SK&F 96365 (1-{β-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl}-1H-imidazole hydrochloride) was investigated. Gd3+ and SK&F 96365 inhibited Ca2+ and Mn2+ inflow stimulated by vasopressin, angiotensin II or phenylephrine. The concentrations of Gd3+ and SK&F 96365 which gave half-maximal inhibition of vasopressin-stimulated Ca2+ inflow were 2 · 10-7 M and 16 · 10-6 M, respectively. The action of Gd3+ on vasopressin-stimulated Ca2+ inflow was rapid (less than 10 s in onset) and reversible. Gd3+ had no effect on Mn2+ inflow in the absence of an agonist and no effect on the ability of vasopressin to release Ca2+ from intracellular stores. SK&F 96365 inhibited Mn2+ inflow in the absence of agonists and vasopressin-induced release of Ca2+ from intracellular stores, but at approximately a 5-fold higher concentration than that which inhibited vasopressin-stimulated divalent cation inflow. It is concluded that Gd3+ and SK&F 96365 (at concentrations below 20 μM) inhibit, in a selective manner, divalent cation movement through the putative cation channel of the hepatocyte receptor-activated Ca2+ inflow system. Gd3+ appears to be the most potent inhibitor of this Ca2+ inflow system so far described.
Original language | English |
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Pages (from-to) | 383-389 |
Number of pages | 7 |
Journal | BBA - Molecular Cell Research |
Volume | 1222 |
Issue number | 3 |
DOIs | |
Publication status | Published - 21 Jul 1994 |
Keywords
- (Rat)
- Calcium ion inflow
- Gadolinium
- Hepatocyte
- SK&F 96365
- Vasopressin