Wilson D R, Honrath U, Sonnenberg H
Am J Physiol. 1983 Jun;244(6):F666-73. doi: 10.1152/ajprenal.1983.244.6.F666.
The effect of furosemide on inner medullary collecting duct chloride reabsorption has not been determined, and the blunting of furosemide action by drugs that inhibit prostaglandin synthesis, while known to occur, has not been examined in detail. The effect of indomethacin and meclofenamate on furosemide diuresis was studied in the rat using clearance and collecting duct microcatheterization methods. Furosemide-treated control animals showed complete inhibition of chloride, sodium, and water reabsorption in the inner medullary collecting duct. Rats given indomethacin or meclofenamate before and during furosemide administration showed marked reduction of the chloriuresis, natriuresis, and diuresis. Reduced delivery of sodium and chloride to the beginning of the inner medullary collecting duct, associated with a decrease in glomerular filtration rate and increased reabsorption in more proximal nephron segments, was largely responsible for the reduced natriuresis and chloriuresis during inhibition of prostaglandin synthesis. In addition, indomethacin increased collecting duct NaCl reabsorption toward normal, but meclofenamate showed no such effect. The results indicate that furosemide inhibits medullary collecting duct reabsorption of chloride, sodium, and water in the rat. The blunting of diuretic action seen with inhibition of prostaglandin synthesis is largely, although not entirely, due to effects of indomethacin and meclofenamate on furosemide action at nephron sites proximal to the collecting duct.
呋塞米对髓质集合管氯重吸收的作用尚未确定，并且已知抑制前列腺素合成的药物会减弱呋塞米的作用，但尚未对此进行详细研究。采用清除率和集合管微插管法在大鼠中研究了吲哚美辛和甲氯芬那酸对呋塞米利尿作用的影响。经呋塞米处理的对照动物显示髓质集合管中氯、钠和水的重吸收完全受到抑制。在给予呋塞米之前及期间给予吲哚美辛或甲氯芬那酸的大鼠，其氯尿、钠尿和利尿作用均显著降低。钠和氯向髓质集合管起始部的输送减少，这与肾小球滤过率降低及近端肾单位节段重吸收增加有关，这在很大程度上导致了抑制前列腺素合成期间钠尿和氯尿的减少。此外，吲哚美辛可使集合管氯化钠重吸收恢复正常，但甲氯芬那酸未显示出这种作用。结果表明，呋塞米可抑制大鼠髓质集合管对氯、钠和水的重吸收。抑制前列腺素合成时所见到的利尿作用减弱，虽然不是完全，但很大程度上是由于吲哚美辛和甲氯芬那酸对呋塞米在集合管近端肾单位部位作用的影响。
