OBJECTIVE: To explore the objective evidence of the corpus biochemical changes in rabbits for postmortem diagnosis of potassium intoxication. METHODS: Rabbits were sacrificed by Infusion of 0.3% KCl at full speed push or 1% KCl at 100 drip/min, respectively, with normal rabbits used as control. Cardiac blood and urine samples were collected before and after potassium infusion to examine the concentrations of various electrolytes (K+, Na+, Ca2+, Mg2+, Cl-, and HCO3-) and to observe the antemortem and postmortem biochemical changes. RESULTS: The mean lethal infusion time in the 0.3%KCl group was longer than that in the 1% KCl group (P = 0.006). The serum concentration of K+ increased while the serum concentrations of Na+, Ca2+, Cl-, and HCO3- decreased after the infusion. There were no statistically significant differences in the whole blood concentration of K+ as well as the serum concentration of Mg2+ between the two groups (P = 0.062). There were statistically significant differences in the concentrations of whole blood K+, as well as serum Na+, Mg2+, and Cl-, but not in the serum K+, Ca2+, and HCO3-. There were no statistically significant differences seen in the urine volumes and the concentrations of all the urine electrolytes between the groups. CONCLUSION Examination of the concentrations of K+ both in the whole blood and serum, as well as Mg2+ in the serum may be helpful for postmortem diagnosis of potassium intoxication.
Animals ; Calcium/urine* ; Electrolytes/urine* ; Forensic Medicine/methods* ; Injections, Intravenous/methods* ; Magnesium/urine* ; Male ; Postmortem Changes ; Potassium/poisoning* ; Potassium Chloride/administration & dosage* ; Rabbits ; Sodium/urine*

In order to further characterize the basic pattern of electrolyte and nitrogen metabolism of the Korean, 24-hour urines were collected from 1,260 male subjects who were randomly selected from three different geographical areas (city, rural and island) in age from 6 to 25. For the city subjects, studies were conducted in both summer and winter for a seasonal comparison, while the other subjects were studied in the autumn only. Of these subjects, blood samples were also obtained from 225. In all groups, the serum composition of electrolytes including proteins was within normal range. The daily urine output which increased as a function of age was somewhat greater in summer than in winter. The daily urine output per unit surface is decreased inversely according to age. On the other hand, the urine osmolality which increased with age was higher in winter than in summer. The daily salt excretion which was greater in summer than in winter increased according to age, although the daily salt excretion per unit surface area was constant regardless of age. The daily potassium excretion was such that the urinary K/Na ratio decreased according to age while it was higher in winter than in summer. Likewise, the daily nitrogen excretion was much greater in winter than in summer while it increased with age. However, the daily nitrogen excretion per unit surface area decreased in older subjects age. In contrast to these seasonal differences in respect to certain electrolytes and nitrogen excretion, there was no distinct geographic difference in these variables. Moreover, many of the above variables changed according to age, but tended to stabilize at the age of approximately 15 years. A comparison of the present data with others indicates that the daily urine output and the daily salt excretion are greater while the urine osmolality, the daily nitrogen excretion and the urinary K/Na ratio are lower in the Korean than in the occidental. Moreover, these results strongly suggest that Korean people acquired a habit of ingesting low-protein and high-salt diets at the age of 6 years or perhaps before.
Adolescent ; Adult ; Asian Continental Ancestry Group ; Child ; Dietary Proteins ; Electrolytes/*urine ; Human ; Korea ; Male ; Nitrogen/*urine ; Seasons ; *Water-Electrolyte Balance

OBJECTIVETo explore the influence factors of salt-sensitive hypertension and to observe changes of blood pressures and urinary sodium and potassium excretion in response to acute oral saline loading among essential hypertensive patients in China.

METHODSEssential hypertensive patients from Beijing Jinzhan second community were included in this study. Salt-sensitivity was determined via the improved Sullivan's acute oral saline loading and furosemide volume-depletion tests. Binary logistic regression analysis was applied to explore influence factors of salt-sensitive hypertension. Acute oral saline loading induced changes on blood pressures and urinary sodium and potassium excretion were observed.

RESULTSSixty-three salt-sensitive hypertensive patients were classified out of a total of 342(18.4%) essential hypertensive patients. Salt-sensitive patients were elder than the non-salt-sensitive patients (P < 0.05) . Binary logistic regression analysis showed that age (OR = 1.744, 95%CI:0.922-3.300, P > 0.05) , gender (OR = 0.728, 95%CI:0.374-1.415, P > 0.05) , total cholesterol level (OR = 1.168, 95%CI:0.882-1.547, P > 0.05) and 24-hour urinary sodium (OR = 0.998, 95%CI:0.995-1.002, P > 0.05) were not influencing factors of salt-sensitivity among essential hypertensive patients. Bivariate general linear models for repeated measures showed that there were significant statistical differences on blood pressures and urinary electrolytes concentrations between the beginning of trials, 2 hours after acute saline loading and 2 hours after furosemide volume-depletion(all P < 0.01). There was a greater blood pressures change in salt-sensitive patients than in non-salt-sensitive patients(all P < 0.01) while urinary electrolytes concentrations change was similar between two groups(all P > 0.05).

CONCLUSIONSAge, gender, total cholesterol level and 24-hour urinary sodium are not influencing factors of salt-sensitivity among essential hypertensive patients in this study. Impaired pressure natriuresis during acute oral saline loading and furosemide volume-depletion tests is presented in salt-sensitive essential hypertensive patients.

Adult ; Aged ; Aldosterone ; blood ; Blood Pressure ; drug effects ; Electrolytes ; urine ; Essential Hypertension ; Female ; Humans ; Hypertension ; physiopathology ; Male ; Middle Aged ; Potassium ; urine ; Sodium Chloride, Dietary ; administration & dosage ; urine

Gitelman's syndrome is a variant of Bartter's syndrome characterized by hypocalciuria and hypomagnesemia. The administration of thiazide diuretics may induce a subnormal increase of urinary Na+ and Cl- excretion in patients with Gitelman's syndrome, consistent with the hypothesis that less Na+ and Cl- than normal is reabsorbed by the thiazide-inhibitable transporter in Gitelman's syndrome. Specific mutations of NaCl cotransporter, coupled with mutant NaCl cotransporter expression studies clearly demonstrated that many of the characteristics of individuals with Gitelman's syndrome are explained by lack of function of NaCl cotransporter. We recently diagnosed a patient with Gitelman's syndrome by performing the thiazide and furosemide tests, and it is suggested that the clearance studies by diuretic administration may be of diagnostic help in Gitelman's syndrome.
Adolescent ; Bartter Syndrome/*diagnosis/metabolism/physiopathology ; *Benzothiadiazines ; Chlorides/blood/urine ; Diuretics/diagnostic use ; Electrolytes/blood/urine ; Female ; Furosemide/diagnostic use ; Humans ; Kidney/*physiopathology ; Kidney Function Tests ; Sodium/blood/urine ; Sodium Chloride Symporter Inhibitors/*diagnostic use ; Sodium Chloride Symporters ; Symporters/metabolism ; Syndrome

The kidneys play a key role in the homeostasis of body water and electrolyte balance. Aquaporin-2 (AQP2) is the vasopressin-regulated water-channel protein expressed at the connecting tubule and collecting duct, and plays a key role in urine concentration and body-water homeostasis through short-term and long-term regulation of collecting duct water permeability. The signaling transduction pathways resulting in the AQP2 trafficking to the apical plasma membrane of the collecting duct principal cells, including AQP2 phosphorylation, RhoA phosphorylation, actin depolymerization, and calciumm obilization, and the changes of AQP2 abundance in water-balance disorders have been extensively studied. Dysregulation of AQP2 has been shown to be importantly associated with a number of clinical conditions characterized by body-water balance disturbances, including hereditary nephrogenic diabetes insipidus (NDI), lithium-induced NDI, electrolytes disturbance, acute and chronic renal failure, ureteral obstruction, nephrotic syndrome, congestive heart failure, and hepatic cirrhosis. Recent studies exploiting omics technology further demonstrated the comprehensive vasopressin signaling pathways in the collecting ducts. Taken together, these studies elucidate the underlying molecular mechanisms of body-water homeostasis and provide the basis for the treatment of body-water balance disorders.
Actins ; Aquaporin 2* ; Aquaporins ; Arginine Vasopressin ; Body Water ; Cell Membrane ; Diabetes Insipidus, Nephrogenic ; Electrolytes ; Heart Failure ; Homeostasis* ; Kidney Failure, Chronic ; Kidney* ; Liver Cirrhosis ; Nephrotic Syndrome ; Permeability ; Phosphorylation ; Ubiquitination ; Ureteral Obstruction ; Urine ; Vasopressins ; Water-Electrolyte Balance