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American Journal of Physiology.... Oct 2022The aim of this study was to investigate layer and species variations in detrusor muscle strip responses to myogenic, neurogenic, and nicotinic, and muscarinic receptor...
The aim of this study was to investigate layer and species variations in detrusor muscle strip responses to myogenic, neurogenic, and nicotinic, and muscarinic receptor stimulations. Strips from bladders of 9 dogs and 6 human organ transplant donors were dissected from inner and outer longitudinal muscle layers, at least 1 cm above urethral orifices. Strips were mounted in muscle baths and maximal responses to neurogenic stimulation using electrical field stimulation (EFS) and myogenic stimulation using potassium chloride (KCl, 120 mM) determined. After washing and re-equilibration was completed, responses to nicotinic receptor agonist epibatidine (10 μM) were determined followed by responses to EFS and muscarinic receptor agonist bethanechol (30 μM) in continued presence of epibatidine. Thereafter, strips and full-thickness bladder sections from four additional dogs and three human donors were examined for axonal density and intramural ganglia. In dog bladders, contractions to KCl, epibatidine, and bethanechol were 1.5- to 2-fold higher in the inner longitudinal muscle layer, whereas contractions to EFS were 1.5-fold higher in the outer (both pre- and post-epibatidine). Human bladders showed 1.2-fold greater contractions to epibatidine in the inner layer and to EFS in the outer, yet no layer differences to KCl or bethanechol were noted. In both species, axonal density was 2- to 2.5-fold greater in the outer layer. Dogs had more intramural ganglia in the adventitia/serosa layer, compared with more internal layers and to humans. These findings indicate several layer-dependent differences in receptor expression or distribution, and neurogenic responses in dog and human detrusor muscles, and myogenic/muscarinic differences between dog versus humans.
Topics: Animals; Bethanechol; Dogs; Electric Stimulation; Humans; Muscarinic Agonists; Muscle Contraction; Muscle, Smooth; Nicotine; Potassium Chloride; Receptors, Muscarinic; Receptors, Nicotinic; Urinary Bladder
PubMed: 36062901
DOI: 10.1152/ajpregu.00084.2022 -
Experimental Physiology May 2021What is the central question of this study? This study presents a new model for studying the rapid onset of severe, acute hyperkalaemia in rats with intact kidney...
NEW FINDINGS
What is the central question of this study? This study presents a new model for studying the rapid onset of severe, acute hyperkalaemia in rats with intact kidney function by administering an intragastric KCl load. What is the main finding and its importance? This new model of intragastric KCl load produces a reliable and reproducible model for studying the rapid onset of severe, acute hyperkalaemia in rats with intact kidney function. We report unprecedented rapid changes (30 min) in ECG, blood pressure and various arterial blood analyses with this new model, providing a solid foundation for future experiments in this field.
ABSTRACT
A variety of animal models have been proposed to study hyperkalaemia, but most of them have meaningful limitations when the goal is to study the effect of potassium overload on healthy kidneys. In this study, we aimed to introduce a new approach for induction of hyperkalaemia in a reliable and reproducible animal model. We used intragastric administration of potassium chloride [KCl 2.3 M, 10 ml/(kg body weight)] to male Holtzman rats (300-350 g) to induce hyperkalaemia. The results showed that this potassium load can temporarily overwhelm the renal and extrarenal handling of this ion, causing an acute and severe hyperkalaemia that can be useful to study the effect of potassium imbalance in a variety of scenarios. Severe hyperkalaemia (>8 meqiv/l) and very profound ECG alterations, characterized by lengthening waves and intervals, were seen as early as 30 min after intragastric administration of KCl in rats. In addition, a transient increase in arterial blood pressure and time-dependent bradycardia were also seen after the KCl administration. No metabolic acidosis was present in the animals, and the potassium ion did not increase proportionally to chloride ion in the blood, leading to an increased anion gap. In conclusion, the results suggest that intragastric KCl loading is a reliable model to promote rapid and severe hyperkalaemia that can be used for further research on this topic.
Topics: Animals; Arrhythmias, Cardiac; Hyperkalemia; Kidney; Male; Potassium; Potassium Chloride; Rats
PubMed: 33651463
DOI: 10.1113/EP089356 -
British Medical Journal Dec 1965
Topics: Humans; Intestinal Diseases; Potassium Chloride; Tablets, Enteric-Coated
PubMed: 5850476
DOI: 10.1136/bmj.2.5477.1546-a -
Journal of Dairy Science Oct 2013Sodium chloride (NaCl) in cheese contributes to flavor and texture directly and by its effect on microbial and enzymatic activity. The salt-to-moisture ratio (S/M) is...
Sodium chloride (NaCl) in cheese contributes to flavor and texture directly and by its effect on microbial and enzymatic activity. The salt-to-moisture ratio (S/M) is used to gauge if conditions for producing good-quality cheese have been met. Reductions in salt that deviate from the ideal S/M range could result in changing culture acidification profiles during cheese making. Lactococcus lactis ssp. lactis or Lc. lactis ssp. cremoris are both used as cultures in Cheddar cheese manufacture, but Lc. lactis ssp. lactis has a higher salt and pH tolerance than Lc. lactis ssp. cremoris. Both salt and pH are used to control growth and survival of Listeria monocytogenes and salts such as KCl are commonly used to replace the effects of NaCl in food when NaCl is reduced. The objectives of this project were to determine the effects of sodium reduction, KCl use, and the subspecies of Lc. lactis used on L. monocytogenes survival in stirred-curd Cheddar cheese. Cheese was manufactured with either Lc. lactis ssp. lactis or Lc. lactis ssp. cremoris. At the salting step, curd was divided and salted with a concentration targeted to produce a final cheese with 600 mg of sodium/100 g (control), 25% reduced sodium (450 mg of sodium/100 g; both with and without KCl), and low sodium (53% sodium reduction or 280 mg of sodium/100 g; both with and without KCl). Potassium chloride was added on a molar equivalent to the NaCl it replaced to maintain an equivalent S/M. Cheese was inoculated with a 5-strain cocktail of L. monocytogenes at different times during aging to simulate postprocessing contamination, and counts were monitored over 27 or 50 d, depending on incubation temperature (12 or 5 °C, respectively). In cheese inoculated with 4 log₁₀ cfu of L. monocytogenes/g 2 wk after manufacture, viable counts declined by more than 3 log₁₀ cfu/g in all treatments over 60 d. When inoculated with 5 log₁₀ cfu/g at 3mo of cheese age, L. monocytogenes counts in Cheddar cheese were also reduced during storage, but by less than 1.5 log10 cfu/g after 50 d. However, cheese with a 50% reduction in sodium without KCl had higher counts than full-sodium cheese at the end of 50 d of incubation at 4 °C when inoculated at 3 mo. When inoculated at 8 mo postmanufacture, this trend was only observed in 50% reduced sodium with KCl, for cheese manufactured with both cultures. This enhanced survival for 50% reduced-sodium cheese was not seen when a higher incubation temperature (12 °C) was used when cheese was inoculated at 3 mo of age and monitored for 27 d (no difference in treatments was observed at this incubation temperature). In the event of postprocessing contamination during later stages of ripening, L. monocytogenes was capable of survival in Cheddar cheese regardless of which culture was used, whether or not sodium had been reduced by as much as 50% from standard concentrations, or if KCl had been added to maintain the effective S/M of full-sodium Cheddar cheese.
Topics: Cheese; Diet, Sodium-Restricted; Flavoring Agents; Food Handling; Food Microbiology; Food Safety; Hydrogen-Ion Concentration; Lactococcus lactis; Listeria monocytogenes; Potassium Chloride; Sodium Chloride, Dietary; Temperature
PubMed: 23910550
DOI: 10.3168/jds.2013-6675 -
Kidney International Sep 1981According to the hypothesis of potassium recycling in the renal medulla, a portion of potassium in fluid in the medullary collecting duct is reabsorbed, trapped in the...
According to the hypothesis of potassium recycling in the renal medulla, a portion of potassium in fluid in the medullary collecting duct is reabsorbed, trapped in the medullary interstitium by countercurrent exchange, and secreted in either the pars recta or descending limb of the juxtamedullary nephron. To examine the effects of an acute change in potassium balance on recycling, we performed a micropuncture study on the exposed papilla of 8 chloride. A second group of 6 rats was studied under identical conditions and infused with potassium chloride and amiloride. In the first group, the fraction of filtered potassium remaining at the end of the juxtamedullary descending limb increased with time to values over 100% concomitantly with the rise in urinary excretion of potassium. A strong association was found between those two variables (P less than 0.025). In the second group, in which the increase in urinary fractional excretion of potassium was prevented by amiloride, the rise in fractional of filtered potassium remaining at the end of the juxtamedullary nephron was abolished. These findings are interpreted as providing further support for the hypothesis of medullary recycling of potassium.
Topics: Amiloride; Animals; Diet; Female; Kidney Medulla; Male; Potassium; Potassium Chloride; Rats; Rats, Inbred Strains
PubMed: 7300124
DOI: 10.1038/ki.1981.145 -
Revista Da Associacao Medica Brasileira... Nov 2019To assess the frequency and severity of prescriptions errors with potentially dangerous drugs (heparin and potassium chloride for injection concentrate) before and after... (Comparative Study)
Comparative Study
OBJECTIVE
To assess the frequency and severity of prescriptions errors with potentially dangerous drugs (heparin and potassium chloride for injection concentrate) before and after the introduction of a computerized provider order entry (CPOE) system.
METHODS
This is a retrospective study that compared errors in manual/pre-typed prescriptions in 2007 (Stage 1) with CPOE prescriptions in 2014 (Stage 2) (Total = 1,028 prescriptions), in two high-complexity hospitals of Belo Horizonte, Brasil.
RESULTS
An increase of 25% in the frequency of errors in Hospital 1 was observed after the intervention (p<0.001). In contrast, a decreased error frequency of 85% was observed in Hospital 2 (p<0.001). Regarding potassium chloride, the error rate remained unchanged in Hospital 1 (p>0.05). In Hospital 2, a significant decrease was recorded in Stage 2 (p<0.001). A reduced error severity with heparin (p<0.001) was noted, while potassium chloride-related prescription severity remain unchanged (p> 0.05).
CONCLUSIONS
The frequency and severity of medication errors after the introduction of CPOE was affected differently in the two hospitals, which shows a need for thorough observation when the prescription system is modified. Control of new potential errors introduced and their causes for the adoption of measures to prevent these events must be in place during and after the implementation of this technology.
Topics: Brazil; Electronic Prescribing; Heparin; Humans; Medical Order Entry Systems; Medication Errors; Potassium Chloride; Retrospective Studies
PubMed: 31800895
DOI: 10.1590/1806-9282.65.11.1349 -
Journal of Clinical Hypertension... Jul 2016The 24-hour urine collection method is considered the gold standard for the estimation of ingested potassium and sodium. Because of the impracticalities of collecting... (Comparative Study)
Comparative Study
The 24-hour urine collection method is considered the gold standard for the estimation of ingested potassium and sodium. Because of the impracticalities of collecting all urine over a 24-hour period, spot urine is often used for epidemiological investigations. This study aims to assess the agreement between spot urine and 24-hour urine measurements to determine sodium and potassium intake. A total of 402 participants aged 25 to 64 years were randomly selected in South Benin. Spot urine was taken during the second urination of the day. Twenty-four-hour urine was also collected. Samples (2-mL) were taken and then stored at -20°C. The analysis was carried out using potentiometric dosage. The agreement between spot urine and 24-hour urine measurements was established using Bland-Altman plots. A total of 354 results were analyzed. Daily sodium chloride and potassium chloride urinary excretion means were 10.2±4.9 g/24 h and 2.9±1.4 g/24 h, respectively. Estimated daily sodium chloride and potassium chloride means from the spot urine were 10.7±7.0 g/24 h and 3.9±2.1 g/24 h, respectively. Concordance coefficients were 0.61 at d=-0.5 g, (d±2SD=-11 g and 10.1 g) for sodium chloride and 0.61 at d=-1 g, (d±2SD=-3.8 g and 1.8 g) for potassium chloride. Spot urine method is acceptable for estimating 24-hour urinary sodium and potassium excretion to assess sodium and potassium intake in a black population. However, the confidence interval for the mean difference, which is too large, makes the sodium chloride results inadmissible at a clinical level.
Topics: Adult; Benin; Female; Humans; Middle Aged; Potassium Chloride; Sensitivity and Specificity; Sodium Chloride; Time Factors; Urine Specimen Collection
PubMed: 26530545
DOI: 10.1111/jch.12722 -
The Journal of Physiology Feb 19741. Five subjects were given 373 test meals of 750 ml. water containing a range of concentrations of glucose or potassium chloride.2. The greater the concentration of...
1. Five subjects were given 373 test meals of 750 ml. water containing a range of concentrations of glucose or potassium chloride.2. The greater the concentration of solute in the meals, the greater was the volume of the test meal recovered from the stomach after a fixed time.3. When the concentrations of the solutes were expressed as m-osmole/l. corrected by osmotic coefficients based on vapour pressures at 37 degrees C, glucose and potassium chloride were indistinguishable in slowing gastric emptying.4. These results are consistent with the regulation of gastric emptying by a duodenal receptor responding to osmotic pressure.5. Potassium chloride was more nauseating than glucose on an osmolar basis.
Topics: Duodenum; Female; Glucose; Humans; Male; Osmolar Concentration; Osmotic Pressure; Potassium Chloride; Sensory Receptor Cells; Stomach
PubMed: 4822585
DOI: 10.1113/jphysiol.1974.sp010476 -
BMC Neuroscience Oct 2023Aspects of glutamate neurotransmission implicated in normal and pathological conditions are predominantly evaluated using in vivo recording paradigms in rats...
BACKGROUND
Aspects of glutamate neurotransmission implicated in normal and pathological conditions are predominantly evaluated using in vivo recording paradigms in rats anesthetized with isoflurane or urethane. Urethane and isoflurane anesthesia influence glutamate neurotransmission through different mechanisms; however, real-time outcome measures of potassium chloride (KCl)-evoked glutamate overflow and glutamate clearance kinetics have not been compared within and between regions of the brain. In order to maintain rigor and reproducibility within the literature between the two most common methods of anesthetized in vivo recording of glutamate, we compared glutamate signaling as a function of anesthesia and brain region in the rat strain most used in neuroscience.
METHODS
In the following experiments, in vivo amperometric recordings of KCl-evoked glutamate overflow and glutamate clearance kinetics (uptake rate and T) in the cortex, hippocampus, and thalamus were performed using glutamate-selective microelectrode arrays (MEAs) in young adult male, Sprague-Dawley rats anesthetized with either isoflurane or urethane.
RESULTS
Potassium chloride (KCl)-evoked glutamate overflow was similar under urethane and isoflurane anesthesia in all brain regions studied. Analysis of glutamate clearance determined that the uptake rate was significantly faster (53.2%, p < 0.05) within the thalamus under urethane compared to isoflurane, but no differences were measured in the cortex or hippocampus. Under urethane, glutamate clearance parameters were region-dependent, with significantly faster glutamate clearance in the thalamus compared to the cortex but not the hippocampus (p < 0.05). No region-dependent differences were measured for glutamate overflow using isoflurane.
CONCLUSIONS
These data support that amperometric recordings of KCl-evoked glutamate under isoflurane and urethane anesthesia result in similar and comparable data. However, certain parameters of glutamate clearance can vary based on choice of anesthesia and brain region. In these circumstances, special considerations are needed when comparing previous literature and planning future experiments.
Topics: Rats; Male; Animals; Isoflurane; Urethane; Glutamic Acid; Rats, Sprague-Dawley; Potassium Chloride; Reproducibility of Results; Anesthetics; Synaptic Transmission; Brain
PubMed: 37817064
DOI: 10.1186/s12868-023-00822-3 -
BMJ (Clinical Research Ed.) Aug 1988
Topics: Ethics, Medical; Female; Fetus; Humans; Potassium Chloride; Pregnancy; Pregnancy, Multiple; Pregnant Women; Risk Assessment; Value of Life
PubMed: 3139132
DOI: 10.1136/bmj.297.6646.433