Paramecium are attracted to ammonium chloride solutions relative to sodium chloride control solutions, but little is known about the mechanisms by which attraction is evoked. A known effect of ammonium solutions in other cell types is an alteration of intracellular pH. We show here that intracellular pH is elevated upon initial exposure to 5 mM NH4Cl, but appears to decline within 10 minutes, b...

The effects of NH4+ on the intracellular pH (pHi) and on the ATP content in isolated perfused rat liver were studied by 31P n.m.r. spectroscopy. In the initial phase of perfusion an average pHi of 7.29 +/- 0.04 was estimated. The presence of low (0.5 mmol/l) and high (10 mmol/l) doses of NH4Cl induced significant intracellular acidification by -0.06 +/- 0.03 and -0.11 +/- 0.03 pH unit respectiv...

The weak base ammonium chloride has been previously reported to inhibit lysosomal movements and phagosome-lysosome (Ph-L) fusion in cultured mouse macrophages (M phi), thus reducing delivery, to an intraphagosomal infection, of endocytosed solutes that have concentrated in secondary lysosomes. We have now addressed the question, whether NH4Cl might affect any direct interaction (if it exists) b...

To maximize T-lymphocyte killing with anti-pan-T-lymphocyte immunotoxin (IT), prepared by linking ricin A-chain to monoclonal antibody (MoAb) T101 (T101-RTA IT), we have established the nature and the extent of parameters that influence the sensitivity of T lymphocytes to the IT. We showed that peripheral blood T lymphocytes, which are much less susceptible than malignant T cells to the T101-RT...

When hepatocytes were freshly isolated from rat liver and incubated for various periods of time at 37 degrees C, the media from the incubation, when completely separated from the cells, actively degraded 125I-insulin. THis soluble protease activity was strongly inhibited by bacitracin but was unaffected by the lysosomatropic agent ammonium chloride (NH4Cl). When hepatocytes were incubated with ...

Four calves (avg wt 161 kg) were surgically fitted with indwelling catheters in the femoral artery and femoral, portal, hepatic and mesenteric veins to study the effects of subclinical ammonia toxicity on portal-drained viscera (PDV) and hepatic (HEP) net flux of key metabolites and pancreatic hormones. Hyperammonemia was induced via administration of ammonium chloride (NH4Cl; 12 mumol.kg BW-1....

Rat chorda tympani (CT) responses to NH4Cl, ammonium acetate (NH4Ac), and ammonium hippurate (NH4Hp) were obtained during simultaneous current and voltage clamping of the lingual field potential. Although functional and developmental similarities for gustation have been reported for NH4+ and K+ salts, we report here that significant differences are discernible in the CT responses to both salts....

PURPOSE To determine whether N-chlorotaurine (NCT) demonstrates antiviral activity against adenovirus (Ad) in vitro and in the Ad5/NZW rabbit ocular model. METHODS The in vitro activity of NCT was evaluated by incubating different Ad serotypes with several concentrations of NCT for 1 hour and determining the reduction in Ad titers. In rabbit study 1, Ad5-infected eyes were treated with 2.5%, ...

Thrombin induces partial secretion (up to 60%) of beta-N-acetyl-D-hexosaminidase (EC 3.2.1.52) from untreated platelets. Preincubation of platelets with 10 mM NH4Cl for up to 2 hr resulted in a time-dependent and marked stimulation of thrombin-induced secretion of both this enzyme and other acid glycosidases from platelets. The enhancement of the thrombin-induced secretion was not due to cell l...