Zelandopam hydrochloride

To elucidate the role of peripheral dopamine D1 receptors in cisplatin-induced acute renal injury, effect of zelandopam (YM435, (-)-(S)-4-(3,4-dihydroxyphenyl)-7,8-dihydroxy-1,2,3,4-tetrahydroisoquinoline hydrochloride hydrate), a selective renal dopamine D1 receptor agonist, on cisplatin-induced acute renal failure in rats was studied. Rats were divided into six groups: control, cisplatin and cisplatin plus zelandopam (30, 100, 300 mg/kg p.o. twice, 75 and 15 min before cisplatin injection) or the free radical scavenger CV-3611 (2-O-octadecylascorbic acid, 10 mg/kg p.o., 75 min before cisplatin injection) treated groups. Rats received intraperitoneal injection of cisplatin at a dose of 5 mg/kg. Four days after cisplatin injection, plasma creatinine, blood urea nitrogen and body weight were measured and the kidneys were removed for histological examination. Cisplatin induced acute renal failure characterized by the increases in plasma creatinine and blood urea nitrogen with tubular damage, and decreased body weight. Zelandopam dose-dependently prevented all these changes. The free radical scavenger CV-3611 significantly attenuated a decrease in body weight and renal dysfunction without reducing tubular damage. The present study is the first demonstration for that a selective dopamine D1 receptor agonist is effective in preventing acute renal failure induced by cisplatin.

Background —To elucidate the roles of vascular D 1 -like receptors in atherosclerosis, the effects of the specific D 1 -like agonists on platelet-derived growth factor (PDGF)-BB–mediated oxidative stress in vascular smooth muscle cells (VSMCs) were studied. Methods and Results —Immunohistochemical studies demonstrated the coexistence of D 1A and D 1B dopamine receptors in VSMCs. Western blotting revealed a band of ≈70 kDa for D 1A and D 1B dopamine receptors. VSMCs stimulated by PDGF-BB exhibited increased oxidative stress directly measured by flow cytometry. These effects were prevented by dopamine, SKF 38393, or YM 435, and this prevention was reversed by Sch 23390. These effects were blocked by a specific protein kinase A (PKA) inhibitor, N -(2-[ p -bromocinnamylamino]ethyl)-5-isoquinolinesulfonamide (H 89). The PDGF-BB–mediated increase in oxidative stress of VSMCs was significantly suppressed by the indirect phospholipase D (PLD) inhibitor suramin or the specific protein kinase C (PKC) inhibitor calphostin C. Both antisense but neither sense nor scrambled oligonucleotides to D 1A and D 1B receptors inhibited dopamine-induced suppression of increase in oxidative stress of VSMCs induced by PDGF-BB. Conclusions —These findings suggest that vascular D 1 -like receptors (D 1A and D 1B receptors) inhibit any increase in oxidative stress of VSMCs, possibly through activation of PKA and suppression of PLD and PKC.