L(+)-lactate transport in perfused rat skeletal muscle: kinetic characteristics and sensitivity to pH and transport inhibitors.
L(+)-lactate transport in perfused rat skeletal muscle: kinetic characteristics and sensitivity to pH and transport inhibitors.
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灌注大鼠骨骼肌中 L( )-乳酸转运：动力学特征以及对 pH 值和转运抑制剂的敏感性。
DOI：
10.1016/0005-2736(88)90434-8
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
M. Rennie
中科院分区：
文献类型：
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作者：
Peter W. Watt;Peter A. MacLennan;H. Hundal;Christy M. Kuret;M. Rennie
我们已经研究了乳酸摄取（净肌肉乳酸积累率）和单向内向运输（成对示踪稀释法测定）灌注皮肤大鼠后肢肌肉。对示踪剂内流的抑制（1 mM（+）-乳酸盐的摄取分数为43.3 ± 3.1%，但50 mM乳酸盐的摄取分数仅为32.9 ± 1.8%）表明示踪剂和天然形式的羧酸盐之间存在转运竞争。d（-）-乳酸盐（50 mM）不抑制示踪剂1（+）-乳酸盐的摄取。丙酮酸盐（25 mM）可抑制示踪乳酸的摄入22%（P< 0.01），但其他五种单羧酸盐均未抑制。将灌注液pH值从7.4改变到6.8，在1 mMl（+）-乳酸时，单向全（+）-乳酸转运增加36%（P< 0.001），而将pH值增加到7.7则使转运减少18%（P< 0.01）。500 μM 4-乙酰氨基-4 ′-异硫氰基二苯乙烯（SITS）（19%）、5 mM α-氰基-4-羟基肉桂酸（CIN）（20-30%）、1 mM阿米洛利（27%）和巯基试剂对氯汞苯磺酸（pCMBS）（26%）可抑制示踪乳酸内流。总的来说，结果表明，乳酸的转移至少涉及两个过程：一个是饱和的，其Vmax为0.84 μmol · min−1· g− 1，表观Km为21 mM，对SITS、CIN和巯基试剂敏感;另一个是不饱和的，对SITS和CIN不敏感，表观速率常数为0.1 min−1。
We have examined lactate uptake (as the rate of net muscle lactate accumulation) and unidirectional inward transport (measured by a paired-tracer dilution method) in muscle of the perfused skinned rat hindlimb. Inhibition of tracer influx (fractional uptake at 1 mMl(+)-lactate, 43.3 ± 3.1% but only 32.9 ± 1.8% at 50 mM lactate) suggested some competition between tracer and native forms of the car☐ylate for transport.d(−)-lactate (50 mM) did not inhibit uptake of tracerl(+)-lactate. Pyruvate (25 mM), but none of five other monocar☐ylates, inhibited uptake of tracer lactate, by 22% (P< 0.01). Altering perfusate pH from 7.4 to 6.8 caused a 36% increase (P< 0.001) in the unidirectionall(+)-lactate transport at 1 mMl(+)-lactate, whereas increasing pH to 7.7 reduced transport by 18% (P< 0.01). Tracer lactate influx was inhibited by 500 μM 4-acetamido-4′-isothiocyanostilbene (SITS) (19%), 5 mM α-cyano-4-hydroxycinnamic acid (CIN) (20–30%), 1 mM amiloride (27%) and by a thiol group reagentp-chloromercuribenzenesulphonic acid (pCMBS) (26%). Overall the results indicate that at least two processes are involved in the transfer of lactate: one, saturable, with aVmaxof 0.84 μmol · min−1· g−1and an apparentKmof 21 mM was sensitive to SITS, CIN, and a thiol group reagent; the other was non-saturable and insensitive to SITS and CIN with an apparent rate constant of 0.1 min−1.
与 L-乳酸转运相关的兔红细胞膜蛋白。
DOI：
--
发表时间：
1982
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Jennings,ML;Adams-Lackey,M
通讯作者：
Adams-Lackey,M