Poynter D, Martin L E, Harrison C, Cook J
Br J Clin Pharmacol. 1976 Aug;3(4 Suppl 3):711-20.
1 The toxicity of labetalol has been studied in mice, rats, rabbits, and dogs, and reproductive studies have been carried out in rats and rabbits. Nothing was observed in any of these species to suggest that patients taking labetalol might be exposed to any toxic hazard. 2 During the reproductive studies 14C-labetalol was used to study placental transfer. Radioactivity was present in the uveal tract of the foetal eye. 3 Radioactive labetalol but not its metabolites was bound to the melanin pigment of the eye. This binding was reversible. It was not possible to saturate the melanin of the cat and dog eye even with prolonged dosing with labetalol. 4 Chloroquine, given orally at doses of 1.5-6 mg/kg/d for 4-7 weeks, produced changes in the cat retina. When oral doses of 20 mg labetalol/d were given to cats for 7 months, no oculotoxic effects were observed. 5 Detailed ophthalmological and histological examinations were carried out on the rats, rabbits, cats and dogs used in these studies. No changes indicative of oculotoxicity were observed. In the reproductive studies no effects were observed in the developing rat or rabbit eye, which could be consequent on the placental transfer of labetalol or its metabolites.
1 已在小鼠、大鼠、兔子和狗身上研究了拉贝洛尔的毒性，并在大鼠和兔子身上进行了生殖研究。在这些物种中均未观察到任何迹象表明服用拉贝洛尔的患者可能面临任何毒性危害。2 在生殖研究中，使用14C-拉贝洛尔来研究胎盘转运。放射性物质存在于胎儿眼睛的葡萄膜中。3 放射性拉贝洛尔而非其代谢产物与眼睛的黑色素结合。这种结合是可逆的。即使长期给猫和狗服用拉贝洛尔，也无法使它们眼睛的黑色素饱和。4 氯喹以1.5 - 6毫克/千克/天的剂量口服给药4 - 7周，会使猫的视网膜发生变化。当给猫每天口服20毫克拉贝洛尔，持续7个月时，未观察到眼毒性作用。5 对这些研究中使用的大鼠、兔子、猫和狗进行了详细的眼科和组织学检查。未观察到表明眼毒性的变化。在生殖研究中，未观察到拉贝洛尔或其代谢产物经胎盘转运对发育中的大鼠或兔子眼睛产生任何影响。
