The role of the lateral intercellular spaces in the control of ion permeation across the rabbit gall bladder

1975 ◽  
Vol 358 (1) ◽  
pp. 27-40 ◽  
Author(s):  
G�nther Wiedner ◽  
Ernest M. Wright
1983 ◽  
Vol 245 (6) ◽  
pp. G816-G823 ◽  
Author(s):  
R. W. Freel ◽  
M. Hatch ◽  
D. L. Earnest ◽  
A. M. Goldner

The effects of a dihydroxy bile salt, taurochenodeoxycholate (TCDC), on the permeability and conductance of isolated, short-circuited segments of the rabbit descending colon were examined using conventional Ussing chamber techniques. Increasing concentrations of TCDC (1℃4 mM) produced dose-dependent increases in sodium backflux (JNas leads to m) and tissue conductance (Gt) when applied to either the mucosal or serosal salines. However, mucosal addition was twice as potent in increasing JNas leads to m and Gt at 4 mM. Tracer experiments indicated that the transepithelial serosal-to-mucosal fluxes of sodium and mannitol are via an aqueous, unrestricted, free-solution pathway, while albumin movements are restricted through this pathway both in the absence and presence of mucosal TCDC. The changes in JNas leads to m, JMans leads to m, and Gt caused by 4 mM mucosal TCDC were largely reversed by rinsing the mucosal chamber with fresh buffer. It was also observed that osmotically induced volume flows in the serosal-to-mucosal direction could offset or reverse the changes in Gt produced by 2 mM mucosal TCDC, suggesting that the enhanced conductance pathway is in series with the lateral intercellular spaces. Taken together, these results suggest that low concentrations of TCDC alter the integrity of tight-junctional complexes between the epithelial cells of the rabbit colon.


Author(s):  
J. McD. Tormey ◽  
E. M. Wright ◽  
A. P. Smulders

The route by which small molecules, such as water, electrolytes and sugars, cross the membranes of epithelial tissues is a central problem in biological transport. Good methods for quantitatively localizing small diffusible molecules within tissues, or for unambiguously demonstrating membrane transport sites, have yet to be developed. In their absence indirect approaches based on anatomical changes have had to be used.The lateral intercellular spaces of gall bladder epithelium were several years ago found to be widely dilated when salt and water were being actively pumped across the tissue. The spaces were collapsed in the absence of transport. Similar phenomena were subsequently observed in several other tissues. This has been widely interpreted as proof that the spaces are the route of fluid transport.


Author(s):  
Mohamed M. Harraz ◽  
Ahmed H. Abouissa

Abstract Background Although gall bladder perforation (GBP) is not common, it is considered a life-threating condition, and the possibility of occurrence in cases of acute cholecystitis must be considered. The aim of this study was to assess the role of multi-slice computed tomography (MSCT) in the assessment of GBP. Results It is a retrospective study including 19 patients that had GBP out of 147, there were 11 females (57.8%) and 8 males (42.1%), aged 42 to 79 year (mean age 60) presented with acute abdomen or acute cholecystitis. All patients were examined with abdominal ultrasonography and contrast-enhanced abdominal MSCT after written informed consent was obtained from the patients. This study was between January and December 2018. Patients with contraindications to contrast-enhanced computed tomography (CT) (pregnancy, acute kidney failure, or allergy to iodinated contrast agents) who underwent US only were excluded. Patients with other diagnoses, such as acute diverticulitis of the right-sided colon or acute appendicitis, were excluded. The radiological findings were evaluated such as GB distention; stones; wall thickening, enhancement, and defect; pericholecystic free fluid or collection; enhancement of liver parenchyma; and air in the wall or lumen. All CT findings are compared with the surgical results. Our results revealed that the most important and diagnostic MSCT finding in GBP is a mural defect. Nineteen patients were proved surgically to have GBP. Conclusion GBP is a rare but very serious condition and should be diagnosed and treated as soon as possible to decrease morbidity and mortality. The most accurate diagnostic tool is the CT, MSCT findings most specific and sensitive for the detection of GBP and its complications.


1992 ◽  
Vol 99 (3) ◽  
pp. 317-338 ◽  
Author(s):  
L Reuss ◽  
B Simon ◽  
C U Cotton

The mechanisms of apparent streaming potentials elicited across Necturus gallbladder epithelium by addition or removal of sucrose from the apical bathing solution were studied by assessing the time courses of: (a) the change in transepithelial voltage (Vms). (b) the change in osmolality at the cell surface (estimated with a tetrabutylammonium [TBA+]-selective microelectrode, using TBA+ as a tracer for sucrose), and (c) the change in cell impermeant solute concentration ([TMA+]i, measured with an intracellular double-barrel TMA(+)-selective microelectrode after loading the cells with TMA+ by transient permeabilization with nystatin). For both sucrose addition and removal, the time courses of Vms were the same as the time courses of the voltage signals produced by [TMA+]i, while the time courses of the voltage signals produced by [TBA+]o were much faster. These results suggest that the apparent streaming potentials are caused by changes of [NaCl] in the lateral intercellular spaces, whose time course reflects the changes in cell water volume (and osmolality) elicited by the alterations in apical solution osmolality. Changes in cell osmolality are slow relative to those of the apical solution osmolality, whereas lateral space osmolality follows cell osmolality rapidly, due to the large surface area of lateral membranes and the small volume of the spaces. Analysis of a simple mathematical model of the epithelium yields an apical membrane Lp in good agreement with previous measurements and suggests that elevations of the apical solution osmolality elicit rapid reductions in junctional ionic selectivity, also in good agreement with experimental determinations. Elevations in apical solution [NaCl] cause biphasic transepithelial voltage changes: a rapid negative Vms change of similar time course to that of a Na+/TBA+ bi-ionic potential and a slow positive Vms change of similar time course to that of the sucrose-induced apparent streaming potential. We conclude that the Vms changes elicited by addition of impermeant solute to the apical bathing solution are pseudo-streaming potentials, i.e., junctional diffusion potentials caused by salt concentration changes in the lateral intercellular spaces secondary to osmotic water flow from the cells to the apical bathing solution and from the lateral intercellular spaces to the cells. Our results do not support the notion of junctional solute-solvent coupling during transepithelial osmotic water flow.


2014 ◽  
Vol 05 (03) ◽  
pp. 246-252 ◽  
Author(s):  
Mumtaz Ahmad Ansari ◽  
Satyendra K. Tiwary ◽  
Uday Pratap Shahi ◽  
Vijay K. Shukla

2017 ◽  
Vol 18 (1) ◽  
pp. 51-53
Author(s):  
Nasreen Sultana ◽  
Zeenat Jabin ◽  
Md Bashir ◽  
Rahima Parveen ◽  
Shamim MF Begum ◽  
...  

Objective: The purpose of this study was to determine whether gall bladder visualization can help to exclude the biliary atresia in hepatobiliary scintigraphic studies of infants with persistent jaundice.Methods: This is a retrospective study carried out at the National Institute of Nuclear Medicine and Allied Sciences (NINMAS). Study subjects include infants with neo-natal jaundice who underwent Hepatobiliary scintigraphies for suspected biliary atresia and study period was 2 years. Food was withheld for 4 hours before the examination. Anterior images of liver and gall bladder were taken after i/v administration of 2 -3 mci 99m Tc labeled Brida (HIDA) at 5 min interval for 2 hours then at 4 hours and 24 hours. Non-visualization of bowel activity in HIDA scan in 24hours delayed images was considered as cases of diagnosis of biliary atresia.Results: Thirty-six patients were included in this retrospective study. Patent biliary channels was seen by scintigraphies in 17(47%) patients and biliary atresia was seen in 19(52%) patients. By abdominal US non- visualization of gall bladder were found in 25(69%) cases and gall bladder visualized in 11(30%) cases. Eight (22%) of 36 patients had biopsy confirmed biliary atresia; all of these had positive scintigraphies and (60%) had positive sonographic findings. Among the 5 false-positive scintigraphies caused by hepatic dysfunction and 2 had normal sonography. Thirty-six patients had periscintigraphic sonography. There were 25/36 (61%) abnormal studies, which included cases with small gallbladder (n = 8) and non-visualized gallbladder (n = 17), but not periportal fibrosis.Conclusion: Gall bladder was usually visible on Hepatobiliary scintigraphy of fasting patients with biliary patency.  Both hepatobiliary scintigraphy and sonography are currently the standard imaging investigations for suspected biliary atresia. The complementary role, in which scintigraphy and sonography are important, and recommend follow-up imaging reassessment before making definitive surgical decisions. This will serve to decrease the frequency of false-positive imaging diagnoses of biliary atresia, and hence, avoid unnecessary surgeries.Bangladesh J. Nuclear Med. 18(1): 51-53, January 2015


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