Disease relevance of lomerizine

• These results suggest that lomerizine may be clinically effective in favorably affecting the optic nerve circulation without producing systemic effects such as the hypotension seen during treatment with other Ca(2+)channel blockers [1].
• These results indicate that lomerizine protects neuronal cells against retinal neurotoxicity both in vivo and in vitro, and that this Ca2+ channel blocker may be useful as a therapeutic drug against retinal diseases that cause neuronal injury, such as normal tension glaucoma (NTG) [2].
• Lomerizine, a Ca2+ channel blocker, reduces glutamate-induced neurotoxicity and ischemia/reperfusion damage in rat retina [2].
• 6. Thus, lomerizine had a greater effect on CBF than on BP and HR and, therefore, it may be clinically effective in conditions associated with circulatory disturbances in the brain, such as migraine, without producing systemic effects (e.g. hypotension) generally seen with other Ca2+ channel blockers [3].
• We investigated the effect of lomerizine, an anti-migraine drug, on the Ba2+ current through voltage-gated Ca2+ channels in rat pheochromocytoma (PC12) cells using a whole-cell voltage-clamp technique [4].

High impact information on lomerizine

• Effects of lomerizine, a calcium channel antagonist, on retinal and optic nerve head circulation in rabbits and humans [5].
• In human studies, the NB obtained from the ONH during the experimental period showed a small but significant increase in the lomerizine-treated group compared with the placebo-treated group, but no significant intergroup difference was detected in the NB obtained from the fovea or in blood pressure, heart rate, or IOP [5].
• RESULTS: Blood flow in the rabbit retina increased significantly in the lomerizine-treated group, but blood flow changed little in the choroid or iris-ciliary body [5].
• Oral 5 mg lomerizine or placebo was administered to volunteers (n=8) in a crossover study, and in areas of the fovea and ONH, the normalized blur (NB), a quantitative index of blood velocity, was measured, together with blood pressure, heart rate, and intraocular pressure (IOP), before and 1.5, 3, 6, and 9 hours after administration [5].
• Morphometric evaluation at 7 days after ischemia/reperfusion showed that treatment with lomerizine (0.1 and 1 mg kg(-1), i.v.) prior to ischemia and again immediately after reperfusion dose-dependently reduced the retinal damage [2].

Chemical compound and disease context of lomerizine

• Verapamil, and even more markedly, lomerizine, increased cellular uptake of calcein transported by P-gp in a P-gp-expressing erythroleukemia cell line, K562-Dox [6].

Biological context of lomerizine

• CONCLUSIONS: Lomerizine increases blood velocity, and probably blood flow, in the ONH and retina in rabbits, and it also increases blood velocity in the ONH in healthy humans, without significantly altering blood pressure or heart rate [5].
• Lomerizine inhibited the Ba2+ current with an IC50 value of 1.9 microM [4].
• CONCLUSIONS: Our findings suggest that lomerizine alleviates secondary degeneration of RGCs induced by an optic nerve crush injury in the rat, presumably by improving the impaired axoplasmic flow [7].

Anatomical context of lomerizine

• Effect of lomerizine, a new Ca(2+)channel blocker, on the microcirculation in the optic nerve head in conscious rabbits: a study using a laser speckle technique [1].
• Histological examination of damaged axons revealed no significant enhancement of the density or total number of axons of the retinal ganglion cells in the lomerizine-treated group [7].
• Inhibitory effect of lomerizine, a diphenylpiperazine Ca2+-channel blocker, on Ba2+ current through voltage-gated Ca2+ channels in PC12 cells [4].
• Lomerizine (0.1 and 0.3 mg/kg, i.v.) significantly increased tissue blood flow in the optic nerve head and the putative blood flow in the long posterior ciliary artery with smaller reduction of blood pressure (0.3 mg/kg, i.v.) and without change in heart rate [8].
• CJZ3, a lomerizine derivative, modulates P-glycoprotein function in rat brain microvessel endothelial cells [9].

Associations of lomerizine with other chemical compounds

• METHODS: Lomerizine (0.1 [n=10] or 0.3 [n=11] mg/kg) or vehicle solution (n=11) was injected intravenously in urethane-anesthetized rabbits, and blood flow in the retina, choroid, and iris-ciliary body was measured by the microsphere method and that in the ONH by the H2 gas-clearance method (0.1 [n=6] or 0.3 [n=9] mg/kg or vehicle, n=6) [5].
• Neither lomerizine nor nilvadipine caused a significant change in intraocular pressure [1].
• We examined the effect of a new Ca(2+)channel blocker, lomerizine (KB-2796), and compared it with that of nilvadipine, on the optic nerve head circulation in conscious rabbits using a laser speckle method [1].
• Increase in doxorubicin cytotoxicity by inhibition of P-glycoprotein activity with lomerizine [6].

Gene context of lomerizine

• In anesthetized rabbits, lomerizine and the other Ca(2+) channel blockers increased the ocular circulation and also inhibited the hypoperfusion induced in optic nerve head tissue by an intravitreous injection of endothelin-1 [10].

Analytical, diagnostic and therapeutic context of lomerizine

• RESULTS: The mean RGC density in the control group decreased to 65.9 +/- 1.32% of the contralateral eye, whereas the systemic application of 10 or 30 mg/kg of lomerizine significantly enhanced the RGC survival to 88.1 +/- 0.38% and 89.8 +/- 0.28%, respectively [7].
• Retinal and choroidal blood flow measurements using the microsphere technique and an SLDF measurements were performed simultaneously in the same rabbit eye before and 30 min after 0.3 mg/kg intravenous injection of lomerizine, a calcium antagonist, or intravitreal injection of 20 microl of 10(-6) M endothelin-1 [11].
• 1. In the present study we examined the effects of a new Ca2+ channel blocker (lomerizine), an antimigraine drug, on cerebral cortical blood flow (CBF) in anaesthetized rats (laser Doppler flowmetry) and on vertebral blood flow in anaesthetized beagle dogs (electromagnetic flowmeter) [3].

References