An Analysis of the Function of the Glomeruli of the Hagfish Mesonephric Kidney
An Analysis of the Function of the Glomeruli of the Hagfish Mesonephric Kidney
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盲鳗中肾肾肾小球的功能分析
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
J. Riegel
中科院分区：
文献类型：
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作者：
J. Riegel
由盲鳗肾脏的肾小球产生的尿液不含胶体，近似于血浆的滤液。然而，加压过滤所需的条件似乎不存在。血浆的平均胶体渗透压至少是肾小球毛细血管平均流体静压的两倍。为了澄清这个谜，肾小球灌注含有胶体的林格氏液。主要结论如下：（1）肾小球毛细血管仅构成灌注通路的一部分，因此滤过分数通常较小（<5%）。(2)肾小球毛细血管似乎是灌注制剂中血管阻力的主要来源。(3)灌注的肾小球血管似乎是两种，不同的灌注压变化的反应。在低压肾小球血管（LPGV）中，压力不超过c。0.4当灌注压力高达1.6 kPa时。在高压肾小球血管（HPGV）中，压力可能超过0.4 kPa，特别是当灌注压升高到“非生理”水平（即1.8至2 kPa）时。HPGV位于肾小球的外周，可能在肾小球前和肾小球后血管之间以及HPGV和更深的LPGV之间提供可变的通畅性通路。(4)评估刺激（例如茶碱，稀释）或抑制（例如哇巴因，2，4-二硝基苯酚）液体分泌组织的化合物和程序对单肾小球滤过率（SGFR）和肾小球毛细血管压（P gc）的影响。在任何灌注中，平均Pgcdidn’t变化显著，并且SGFR在大多数灌注中的比例降低，这可能是由于通过肾小球的流量减少。腺嘌呤（5 × 10-6 M）似乎增加了通过肾小球毛细血管的流量。当灌注液中含有肾上腺素以及哇巴因和2，4-二硝基苯酚时，SGFR减少，在哇巴因的情况下，这似乎是由于对肾小球上皮的直接影响。
Urine produced by glomeruli of the hagfish kidney is colloid-free and approximates a filtrate of the blood plasma. However, conditions necessary for pressure filtration appear to be absent. Average colloid osmotic pressure of the blood plasma is at least double the average hydrostatic pressure in the glomerular capillaries. To clarify this enigma, glomeruli were perfused with colloid-containing Ringer. The principle findings follow: (1) Glomerular capillaries form only part of the perfusion pathway, so that the filtration fraction usually was small (<5%). (2) Glomerular capillaries appeared to be the major source of vascular resistance in the perfused preparation. (3) Perfused glomerular vessels appeared to be of two kinds, which differed in their response to perfusion pressure changes. In low-pressure-glomerular vessels (LPGV), pressure did not exceed c. 0.4 kPa when perfused at pressures up to 1.6 kPa. In high-pressure-glomerular vessels (HPGV), pressure could exceed 0.4 kPa, especially when the perfusion pressure was elevated to ‘unphysiological’ levels (i.e. 1.8 to 2 kPa). The HPGV lie at the periphery of the glomeruli and may provide a variable-patency pathway between preglomerular and postglomerular vasculature and between HPGV and the more deeply lying LPGV. (4) Assessments were made of the effects upon single-glomerulus-filtration rate (SGFR) and glomerular-capillary pressure (P gc) of compounds and procedures that stimulate (e.g. theophylline, dilution) or inhibit (e.g. ouabain, 2,4-dinitrophenol) fluid-secreting tissues. Average P gcdid not vary significantly in any perfusion, and SGFR was reduced in a proportion of most perfusions probably due to reduced flow through the glomeruli. Adenaline (5 x 10-6 M) appeared to increase flow through the glomerular capillaries. When perfusion fluid contained adrenaline as well as ouabain and 2,4-dinitrophenol, SGFR diminished, and in the case of ouabain, this appeared to be due to a direct effect on the glomerular epithelium.
Myxine glutinosa 单个分离的灌注肾小球的过滤特性。
DOI：
10.1159/000173773
发表时间：
1993
期刊：
Renal physiology and biochemistry
影响因子：
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作者：
Fels,LM;Sanz-Altamira,PM;Decker,B;Elger,B;Stolte,H
通讯作者：
Stolte,H