Water Transport in the Lacrimal Gland

描述(申请人提供)：泪腺分泌的液体是泪液的重要组成部分，据估计约占沐浴角膜的液体体积的50%(Walcott，1998)。最近对小鼠泪腺产生液体的原位测量表明，刺激流率为0.2-0.6微升/分钟(Walcott等人，2002；Paranyuk等人，2001；Moore等人，2000)。我们的初步数据表明，NKCC1的Na+、K+、2CI-共转运体和BKCa通道在泪腺的液体产生中起重要作用。我们建议使用基因敲除小鼠和NZB小鼠(流体流动受损，Paranyuk等人，2001)来研究它们在泪腺产生液体中各自的作用。此外，我们建议使用PKC的激活剂和抑制剂来描述它在调节NKCC1共转运体和BKCa通道中的作用。这两个系统都已被证明受到PKC的影响/调节/调节(Standen和Quayle，1998；周等人，2001；Clerice等人，1995)。我们的建议侧重于解决以下假设： 目的1假说：阻断盐共转运体(NKCC1)将显著减少对照组的刺激液体流量，但与NKCC1基因敲除的流量相似。我们还将比较和对比NZB的控制和淘汰赛。我们建议使用NZB，因为我们的初步结果表明，NZB腺泡细胞中NKCC1的数量明显少于对照组。 目的2：假设：顶膜BKCa通道有助于泪腺正常的液体产生。我们将测试对照(C57)和BKCa Beta 1基因敲除小鼠。 目的3：假说：PKC活性通过调节K通道和/或NKCC1转运蛋白来影响液体产生。我们将测试控件NZB和两个敲除(Beta1和NKCC1)。

DESCRIPTION (provided by applicant): Fluid secreted by the lacrimal gland is an essential component of tears and is estimated to contribute approximately 50% of the liquid volume bathing the cornea (Walcott, 1998). Recently in situ measurements of fluid production from the lacrimal glands of mice have demonstrated stimulated flow rates of 0.2-0.6 uL/minute (Walcott et al., 2002; Paranyuk et al., 2001; Moore et al, 2000). Our preliminary data indicates that the NKCC1 Na+, K+, 2CI- co-transporter and Bkca channels play important roles in fluid production of the lacrimal gland. We propose the use of knockout mice along with NZB mice (compromised fluid flow, Paranyuk et al., 2001) to study their respective roles in fluid production by the lacrimal gland. Further we propose the use of activators and inhibitors of PKC to delineate its role in the regulation of the NKCC1 co-transporter and Bkca channel. Both systems have been shown to be influenced/moduate/regulate by PKC (Standen and Quayle, 1998;Zhou et al., 2001; Clerice etal., 1995). Our proposal is focused on addressing the following hypotheses: Aim 1 Hypothesis: Basolateral blockade of the salt co-transporter (NKCC1) will significantly reduce stimulated fluid flow in controls but will be similar to NKCC1 knockout flow rates. We will also compare and contrast control and knockouts with NZB. We propose the use of NZB because our preliminary results indicates that the NZB acinar cells have significantly less amounts of NKCC1 than controls. Aim 2: Hypothesis: Apical membrane BKca channels contribute to normal fluid production of the lacrimal gland. We will test control (C57) and Bkca Beta 1 knockout mice. Aim 3: Hypothesis: PKC activity affects fluid production via regulation of K channels and/or NKCC1 transporters. We will test controls, NZB and the two knockouts (Beta1 and NKCC1).