The effect of lifarizine (RS‐87476), a novel sodium and calcium channel modulator, on ischaemic dopamine depletion in the corpus striatum of the gerbil

1

Unilateral ligation of the right common carotid artery in the anaesthetized gerbil for 3 h caused a 62.7% decrease in ipsilateral dopamine in the corpus striatum from 1.40 (± 0.13, n = 27) μg g⁻¹ in the non‐ischaemic hemisphere to 0.47 (± 0.07, n = 27) μg g⁻¹ in the ischaemic hemisphere (all results are expressed as mean ± s.e.mean). In sham‐operated animals there were no differences in the dopamine levels (1.31 ± 0.14 μg g⁻¹, n = 11, left; 1.27 ± 0.13 μg g⁻¹, n = 11 in the right hemisphere). Animals with intact communicating arteries in the circulus arteriosus were excluded.

Unilateral ligation of the right common carotid artery in the anaesthetized gerbil for 3 h caused a 62.7% decrease in ipsilateral dopamine in the corpus striatum from 1.40 (± 0.13, n = 27) μg g⁻¹ in the non‐ischaemic hemisphere to 0.47 (± 0.07, n = 27) μg g⁻¹ in the ischaemic hemisphere (all results are expressed as mean ± s.e.mean). In sham‐operated animals there were no differences in the dopamine levels (1.31 ± 0.14 μg g⁻¹, n = 11, left; 1.27 ± 0.13 μg g⁻¹, n = 11 in the right hemisphere). Animals with intact communicating arteries in the circulus arteriosus were excluded.

Lifarizine (RS‐87476; 250, 500, but not 50, μg kg⁻¹, i.p.) protected against this dopamine depletion showing only a 9.2% decrease at 250 μg kg⁻¹, i.p. (P < 0.01) and no decrease at 500 μg kg⁻¹, i.p. (P < 0.01).

Nicardipine (250 μg kg⁻¹, p.o.) was effective when administered chronically once daily for 10 days (26.6% decrease, P < 0.05) but not when administered acutely at 50 μg kg⁻¹, i.p.

DOI: 10.1111/j.1476-5381.1993.tb13549.x

View this article

• Full article (html)
• Enhanced article (html)
• PDF
• References