Factors determining superficial nephron filtration in the mature, growing rat.
Factors determining superficial nephron filtration in the mature, growing rat.
复制标题
决定成熟、生长大鼠浅表肾单位滤过的因素。
DOI：
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发表时间：
1977
影响因子：
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通讯作者：
R. Blantz
中科院分区：
文献类型：
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作者：
B. J. Tucker;R. Blantz
在39只体重93 ~ 335 g、40 ~ 140日龄的Munich-Wistar大鼠中，研究了决定和引起成熟生长期大鼠浅表肾单位肾小球滤过率（sngfr）增加的因素，用微量蛋白法测定肾小球表面毛细血管（PG）至Bowman's间隙（Pt）的流体静压梯度（Δ P）及相应的肾小球压力（PI）。异环磷酰胺血浆膨胀（PV）阻止了滤过-压力平衡（EFP），并允许计算肾小球渗透系数（LpA），其中sngfr = EFP-LpA，EFP = Δ P-pi。sngfr增加与肾单位血浆流量（rpf）（r = 0.81，P <0.001）和LpA（r = 0.71，P <0.001）相关性最好。rpf的增加是因为传入和传出电阻的平行减少（斜率= 0.89 +/- 0.09，r = 0.86，P小于0.001），这也产生了PG和deltaP随生长的恒定性。rpf与LpA的比值保持恒定，生长允许EFP保持相对不变（r = 0.14，P> 0.4）。在LPA的增加应允许过滤压力平衡坚持在水缺乏大鼠尽管rpf随着增长而增加。随着年龄的增长，Δ P是恒定的，因此对sngfr的增加没有贡献。
Factors that determine and cause an increased glomerular filtration rate in superficial nephrons (sngfr) in the mature, growing rat were examined in 39 Munich-Wistar rats, ranging from 93 to 335 g in body weight, from 40 to 140 days in age, and in sngfr, from 15 to 78 nl/min. Hydrostatic pressure gradient (delta P) from glomerular capillary (PG) to Bowman's space (Pt) was measured in surface glomeruli and pertinent oncotic pressures (pi) by microprotein methods. Isoncotic plasma expansion (PV) prevented filtration-pressure equilibrium (EFP) and permitted calculation of glomerular permeability coefficient (LpA) where sngfr = EFP-LpA, and EFP = delta P - pi. Increased sngfr correlated best with nephron plasma flow (rpf) (r = 0.81, P less than 0.001) and LpA (r = 0.71, P less than 0.001). The rpf increased because of parallel reductions in afferent and efferent resistances (slope = 0.89 +/- 0.09, r = 0.86, P less than 0.001), which also produced a constancy of PG and deltaP with growth. The ratio of rpf to LpA remained constant with growth permitting EFP to remain relatively unchanged (r = 0.14, P greater than 0.4). The increase in LpA should permit filtration-pressure equilibrium to persist in the hydropenic rat in spite of increases in rpf with growth. deltaP was constant with increasing age and therefore did not contribute to the increase in sngfr.