Properties of the luminal membrane of isolated perfused rat pancreatic ducts
Properties of the luminal membrane of isolated perfused rat pancreatic ducts
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离体灌注大鼠胰管管腔膜的特性
DOI：
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发表时间：
1988
期刊：
影响因子：
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通讯作者：
R. Greger
中科院分区：
文献类型：
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作者：
I. Novak;R. Greger
本研究的目的是研究HCO 3 −通过何种转运机制穿过胰管细胞的管腔膜，以及细胞如何对二丁酸环腺苷酸（db-cAMP）刺激作出反应。为此目的，一个新开发的制备分离和灌注内和小叶间导管的大鼠胰腺。通过电生理技术监测上皮对抑制剂和激动剂的反应。在未受刺激的导管的浴侧添加HCO 3 −/CO2，使基底外侧膜（PDbl）上的PD去极化约9 mV，这也是在先前的研究中观察到的[21]。这种HCO 3 −效应被Cl−通道阻断剂或输注到导管内腔的SITS消除：i. e. 5-硝基-2-（3-苯丙氨基）-苯甲酸（NPPB，10−5 M）使PDbl超极化8.2±1.6 mV（n=13）; 3′，5-二氯二苯胺-2-羧酸（DCl-DPC，10−5 M）使PDbl超极化10.3±1.7 mV（n=10）; SITS使PDbl超极化7.8±0.9 mV（n=4）。在存在HCO 3 −/CO2浴的情况下，用dbcAMP刺激导管导致PDbl去极化，导管内腔变得更负，管腔膜的电阻分数降低。与forskolin（10−6 M）一起，db-cAMP（10−4 M）引起PDbl快速去极化33.8±2.5 mV（n=6）。当在HCO 3 −/CO2浴中单独给予db-cAMP（5×10−4 M）时，PDbl去极化25.3±4.2 mV（n=10）。在不存在外源性HCO 3 −的情况下，db-cAMP也使PDbl去极化24.7±3.0 mV（n=10）。目前的数据表明，在胰管细胞的管腔膜中，存在与Cl−/HCO 3 −反向转运平行的Cl−传导。二丁酰环腺苷酸可增加管腔膜的Cl−电导。结合我们目前的结果和最近获得的基底外侧膜[21]的数据，提出了胰腺HCO 3 −转运的初步模型。
The aim of the present study was to investigate by what transport mechanism does HCO3− cross the luminal membrane of pancreatic duct cells, and how do the cells respond to stimulation with dibytyryl cyclic AMP (db-cAMP). For this purpose a newly developed preparation of isolated and perfused intra-and interlobular ducts of rat pancreas was used. Responses of the epithelium to inhibitors and agonists were monitored by electrophysiological techniques. Addition of HCO3−/CO2 to the bath side of nonstimulated ducts depolarized the PD across the basolateral membrane (PDbl) by about 9mV, as also observed in a previous study [21]. This HCO3− effect was abolished by Cl− channel blockers or SITS infused into the lumen of the duct: i. e. 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB, 10−5 M) hyperpolarized PDbl by 8.2±1.6 mV (n=13); 3′,5-dichlorodiphenylamine-2-carboxylic acid (DCl-DPC, 10−5 M) hyperpolarized PDbl by 10.3±1.7 mV (n=10); and SITS hyperpolarized PDbl by 7.8±0.9 mV (n=4). Stimulation of the ducts with dbcAMP in the presence of bath HCO3−/CO2 resulted in depolarization of PDbl, the ductal lumen became more negative and the fractional resistance of the luminal membrane decreased. Together with forskolin (10−6 M), db-cAMP (10−4 M) caused a fast depolarization of PDbl by 33.8±2.5 mV (n=6). When db-cAMP (5×10−4 M) was given alone in the presence of bath HCO3−/CO2, PDbl depolarized by 25.3±4.2 mV (n=10). In the absence of exogenous HCO3−, db-cAMP also depolarized PDbl by 24.7±3.0 mV (n=10). The present data suggest that in the luminal membrane of pancreatic duct cells there is a Cl− conductance in parallel with a Cl−/HCO3− antiport. Dibutyryl cyclic AMP increases the Cl− conductance of the luminal membrane. Taking together our present results, and the recent data obtained for the basolateral membrane [21], a tentative model for pancreatic HCO3− transport is proposed.
二苯胺-2-羧酸盐可阻断 Necturus 胆囊上皮细胞中的 Cl(-)-HCO3- 交换。
DOI：
10.1152/ajpcell.1987.253.1.c79
发表时间：
1987
期刊：
The American journal of physiology
影响因子：
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作者：
Reuss,L;Costantin,JL;Bazile,JE
通讯作者：
Bazile,JE