【摘要】 给清醒兔ⅳ输注谷酰多巴（GD）25,和100μg·kg^-1min^-1,MAP、HR和动脉血浆多巴胺（DA）浓度无显著变化,尿DA排泌率和肾DA增加,动脉血浆GD和l-多巴分别达到3.2±0.8μg·ml^-1和10.1±5.1ng·ml^-1,肾脏和肾外去甲肾上腺素（NE）溢出率均降低,肾NE增加,作为具有相对肾脏选择性的DA前体,GD能抑制清醒家兔肾脏及肾外交感神经活性。更多还原

【Abstract】 Renal and total norepinephrine (NE) spillover rates were studied with [3H] NE kinetic method during graded r-l-glutamyl-l-dopa (gludopa) iv infusion in conscious rabbits- Mean arterial pressure (MAP) and heart rate (HR) remained constant during the experiment. Gludopa iv infusion at 25 and 100 μg · kg-1 · min-1 produced marked increases in urinary dopamine (DA) excretion and renal DA content. Although renal venous DA rose after gludopa infusion, the arterial DA was not significantly altered. Arterial plasma gludopa and levodopa levels reached 0. 9+0. 5, 3. 2 +0.8 μg ·ml-1 and 3.0+1.8, 10. 1 μ5.1 ng · ml-1 at the lower and higher gludopa doses, respectively. Gludopa elicited a pronounced dose-related fall in renal NE spillover, which only accounted for about one half of the reduction in overall NE spillover rate. Renal NE content was doubled. These results indicated that gludopa decreased the renal and ex-trarenal NE spillover to plasma. This reduction may be mediated by intrarenally synthesized DA via presynaptic DA-2 and a-2 receptors, but could also be explained by some central tympatho-inhibitory media-更多还原