Direct and specific inhibition of constitutive nitric oxide synthase uniquely regulates brush border membrane Na-absorptive pathways in intestinal epithelial cells

Publication date: 1 September 2018Source: Nitric Oxide, Volume 79Author(s): Balasubramanian Palaniappan, Uma SundaramAbstractPharmacological manipulations of constitutive nitric oxide (cNO) levels have been shown to have variable effects on Na absorption in vivo and in vitro in different tissues. Species differences, untoward in vivo effects (e.g. ENS, blood flow) and pharmacological non-specificity may account for these confounding observations. Thus, to directly and specifically determine the effect of cNO on brush border membrane Na/H exchange (NHE3) and Na-dependent glucose co-transport (SGLT-1), we inhibited cNO synthase (NOS3) with its siRNA in rat small intestinal epithelial cells (IEC-18) in vitro. As expected, intracellular cNO levels were reduced in siRNA NOS3 transfected cells. In these cells, SGLT-1 was significantly reduced compared to control. In contrast, NHE3 was significantly increased in siRNA NOS3 transfected cells. To determine if SGLT-1 changes were secondary to altered Na/K-ATPase, its activity was measured and found to be increased in NOS3 silenced cells. The mechanism of inhibition of SGLT-1 was secondary to diminished affinity of the co-transporter for glucose in NOS3 silenced cells. In contrast, the mechanism of stimulation of NHE3 is by increasing BBM exchanger numbers in siRNA NOS3 cells while the affinity was unaffected. Western blot studies of immunoreactive BBM proteins also confirmed the kinetic studies. All these data indic...
Source: Nitric Oxide - Category: Chemistry Source Type: research

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Source: Annals of Human Biology - Category: Biology Tags: Ann Hum Biol Source Type: research
Authors: Liew M, Rowe LR, Szankasi P, Paxton CN, Kelley T, Toydemir RM, Salama ME PMID: 30027711 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Kim YJ, Ko JM, Song J, Lee KA PMID: 30027710 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Oh J, Yoo IY, Song DJ, Lee JW, Kim YJ, Ki CS, Lee NY, Huh HJ PMID: 30027709 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Sebastian S, Malhotra R, Sreenivas V, Kapil A, Chaudhry R, Dhawan B PMID: 30027708 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Kim JH, Lee E, Lee Y PMID: 30027707 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Heo ST, Kwon KT, Yoo JR, Choi JY, Lee KH, Ko KS PMID: 30027706 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
Authors: Shin KH, Lee HJ, Kim HH, Hong YJ, Park KU, Kim MJ, Kwon JR, Choi YS, Kim JN Abstract Frequencies of red blood cell (RBC) blood group antigens differ by ethnicity. Since the number of immigrants is increasing in Korea, RBC antigens should be assessed in children/youths with parents of different ethnicities to ensure safe transfusions. We investigated the frequency of RBC antigens, except for ABO and RhD, in 382 children and youths with parents having Korean and non-Korean ethnicities. Subjects were divided into those with ethnically Korean parents (Korean group; N=252) and those with at least one parent of ...
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
CONCLUSIONS: rs3761549, rs5902434, and rs2232365 are associated with an increased risk of acute GVHD and decreased risk of post-HSCT infection. PMID: 30027704 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
CONCLUSIONS: Our algorithm omitting weak D testing in D- patients with C-E- phenotype may be a cost-effective testing strategy in Korea. PMID: 30027703 [PubMed - in process]
Source: Annals of Laboratory Medicine - Category: Laboratory Medicine Tags: Ann Lab Med Source Type: research
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