==================================BSR40================================== 40. What is the relationship between total body potassium (measured by K-40) and body composition, in humans. Key words: K-40, body composition, body fat, lean body mass. 1 UI - 87084064 AU - Gray JM ; East BW ; Robertson I ; Preston T ; Lawson DH TI - Whole-body composition in patients with angina pectoris receiving long-term treatment with the nonselective beta-receptor blocking drug nadolol. AB - Nadolol is a nonselective beta-adrenergic receptor antagonist used on a long-term basis for therapy of angina and hypertension. It has been reported to increase renal blood flow in humans. Theoretically, this could lead to an increase in glomerular filtration rate and improved renal sodium handling. The present study was designed to test whether patients receiving long-term nadolol therapy exhibited changes in whole-body composition that might arise as a consequence. Nine nadolol recipients with angina were followed for up to one year, and serial assessments were made of glomerular filtration rates and whole-body composition using in vivo neutron activation analysis to assess nitrogen, oxygen, sodium, potassium, chlorine, phosphorous, and calcium. No significant changes in these elements were observed. We conclude that any effect of nadolol on renal blood flow in short-term studies is not associated with significant changes in body composition measured over a period of one year. MH - Adult ; Aged ; Angina Pectoris/*DRUG THERAPY ; Body Composition/*DRUG EFFECTS ; Body Water/METABOLISM ; Calcium/METABOLISM ; Diet ; Female ; Human ; Male ; Middle Age ; Nadolol/*THERAPEUTIC USE ; Nitrogen/ METABOLISM ; Potassium/METABOLISM ; Sodium/METABOLISM ; Support, Non-U.S. Gov't SO - J Clin Pharmacol 1986 Nov-Dec;26(8):605-10 2 UI - 87011174 AU - Spady DW ; Filipow LJ ; Overton TR ; Szymanski WA TI - Measurement of total body potassium in premature infants by means of a whole-body counter. AB - This paper describes a whole-body counter (WBC) specially designed to measured total body potassium (TBK) infants under 4,500 g. The counter is a "shadow shield: design and consists of a single 10 cm X 10 cm X 45 cm NaI(Tl) crystal, positioned lengthwise and shielded from environmental background radiation by a minimum of 10 cm of lead. The standard error of counting for a 2,000-s counting period is 19.9% for a 1,000-g infant and 11.9% for a 2,000-g infant. TBK of stillborn pigs, measured by the WBC, agreed to an average of 3% of TBK determined by carcass analysis in the same animals. A total of 118 measurements of TBK have been made in 50 premature infants ranging in weight between 1,100 and 3,600 g and in age between 2 and 75 days. The observed relationship of TBK with weight is described by the equation: TBK (mEq) = 0.0433Wt (g + 1.57 r = 0.92. Potassium retention per gram weight gain is estimated to be 0.043 mEq. The obtained TBK values agree well with values published by other workers but extend the range of measurement to 1,100 g. MH - Animal ; Birth Weight ; *Body Composition ; Human ; Infant, Newborn ; Infant, Premature/*METABOLISM ; Potassium/*METABOLISM ; Support, Non-U.S. Gov't ; Swine ; Whole Body Counting/*INSTRUMENTATION SO - J Pediatr Gastroenterol Nutr 1986 Sep-Oct;5(5):750-5 3 UI - 86307128 AU - McGuire EA ; Young VR TI - Nutritional edema in a rat model of protein deficiency: significance of the dietary potassium and sodium content. AB - The importance of the levels of dietary sodium and potassium in the etiology of gross nutritional edema in a rat model was explored. For this purpose a mineral mixture (EAM) was designed to permit changing the levels of sodium and potassium while maintaining other components of the mixture. The mixture supplied (as % of diet) 0.075 sodium and 0.270 potassium. In study 1 the EAM mixture was found to support adequate growth (approximately 6 g/d) in well-nourished rats. In study 2 the effects of feeding the diet in either agar gel or dry form were explored. The agar gel diet did not aggravate disturbances in body water balance in rats receiving low protein (0.75 and 1.0% lactalbumin) diets for 20 wk. In study 3 the effects of changes in the sodium and potassium content were evaluated with respect to development of edema and body composition. Excessive levels of sodium or potassium (each 493 mg/100 g diet) in the low protein diet (0.5% lactalbumin) increased mortality and the prevalence of gross edema. When dietary sodium and potassium were closer to the estimated requirement for the rat (0.075% and 0.270%, respectively) there was no development of visible edema in protein-restricted rats. Measurements of exchangeable body sodium, total body water and extracellular and intracellular fluid spaces in the animals indicated that fluid and electrolyte changes result largely from dietary protein restriction alone. However, these changes only proceed to a condition of visible edema where an excessive or unbalanced intake of sodium and potassium is superimposed upon protein deficiency. MH - Animal ; Body Composition ; Body Water/METABOLISM ; Body Weight ; *Diet ; Disease Models, Animal ; Edema/*ETIOLOGY ; Extracellular Space/METABOLISM ; Intracellular Fluid/METABOLISM ; Male ; Potassium/*ADMINISTRATION & DOSAGE/METABOLISM ; Protein Deficiency/*COMPLICATIONS ; Rats ; Sodium/ *ADMINISTRATION & DOSAGE/METABOLISM SO - J Nutr 1986 Jul;116(7):1209-24 4 UI - 86305227 AU - Belyea RL ; Babbitt CL ; Sedgwick HT ; Zinn GM TI - Body protein losses estimated by nitrogen balance and potassium-40 counting. AB - Body protein losses estimated from N balance were compared with those estimated by 40K counting. Six nonlactating dairy cows were fed an adequate N diet for 7 wk, a low N diet for 9 wk, and a replete N diet for 3 wk. The low N diet contained high cell wall grass hay plus ground corn, starch, and molasses. Soybean meal was added to the low N diet to increase N in the adequate N and replete N diets. Intake was measured daily. Digestibilities, N balance, and body composition (estimated by 40K counting) were determined during each dietary regimen. During low N treatment, hay dry matter intake declined 2 kg/d, and supplement increased about .5 kg/d. Dry matter digestibility was not altered by N treatment. Protein and acid detergent fiber digestibilities decreased from 40 and 36% during adequate N to 20 and 2%, respectively, during low N. Fecal and urinary N also declined when cows were fed the low N diet. By the end of repletion, total intake, fiber, and protein digestibilities as well as N partition were similar to or exceeded those during adequate N intake. Body protein (N) loss was estimated by N balance to be about 3 kg compared with 8 kg by 40K counting. Body fat losses (32 kg) were large because of low energy digestibility and intake. Seven kilograms of body fat were regained during repletion, but there was no change in body protein. MH - Animal ; Body Composition ; Cattle ; Dietary Proteins/ADMINISTRATION & DOSAGE ; *Energy Metabolism ; Female ; Isotope Labeling ; Nitrogen/ *PHYSIOLOGY ; Potassium Radioisotopes ; Proteins/*METABOLISM SO - J Dairy Sci 1986 Jul;69(7):1817-23 5 UI - 86286369 AU - Spady DW ; Atrens MA ; Szymanski WA TI - Effects of mother's smoking on their infants' body composition as determined by total body potassium. AB - It has been suggested that the lower birth weight of newborn infants of mothers who smoke is due mainly to a deficit of lean body mass (LBM). We tested this hypothesis by measuring total body potassium, thus deriving the LBM and fat mass, of newborn infants of mothers who smoked (I-SM; n = 32) or did not smoke (I-NSM; n = 46). Mothers who smoked were significantly younger than nonsmoking ones (25.4 and 28.9 yr, respectively) and with less years of education, but were similar in other parameters examined. The 78 infants, all singleton, were studied within 1 to 3 days of birth. The I-SM had significantly reduced birth weight, length, and head circumference but there was no difference in skinfold thickness. We measured total body potassium with a whole-body counter specially made for use with infants. Mean absolute total body potassium was significantly greater in the I-NSM, but the concentration in relation to weight was not different. Assuming 1 kg LBM to contain 52.1 mmol potassium, the mean LBM was 3028 g in the I-NSM and 2739 in the I-SM; mean fat mass was similar in both groups. Multiple regression analysis revealed an independent negative effect of mother's smoking on birth weight and LBM. This unequal reduction in LBM indicates a complex effect of smoking, probably mediated by alterations in protein synthesis and adipocyte metabolism. It may relate to the higher morbidity rates in infants of mothers who smoke. MH - Adipose Tissue ; *Birth Weight ; Body Composition ; Female ; Human ; Potassium/ANALYSIS ; Pregnancy ; *Smoking ; Support, Non-U.S. Gov't SO - Pediatr Res 1986 Aug;20(8):716-9 6 UI - 86274903 AU - Lohman TG TI - Applicability of body composition techniques and constants for children and youths. AB - This review has focused on the chemical immaturity of children and the implications for body composition estimates. Prepubescent and pubescent children deviate considerably in fat-free body composition from the adult reference male, and this has lead investigators to overestimate body fatness in this population using conventional body composition formulas. The use of multicomponent approaches to body composition to obtain more accurate estimates of body fatness in children has provided new information on the body composition of this population. Sex- and age-specific constants, to replace those derived from the reference male, are suggested for further testing and verification as well as for use in the clinical setting. The chemical immaturity in children has its greatest effect on estimating the extent of obesity in children 6 to 11 years of age and in estimating body fatness in the lean, athletic, prepubescent population. Previous estimates of the growth rate of fat and fat-free body are also affected by chemical immaturity. Further research is needed to study the impact of physical activity and inactivity on the composition of the fat-free body during growth, to develop constants for more accurate estimates of fatness in physically active samples of all ages and to validate the constants presented in the less active populations. Future research with multicomponent body composition systems in all populations of children and youth is essential for progress in this area. Results will have an important contribution to the estimation of childhood obesity, prediction of minimal weight in the athletic population and estimates of growth rate of fat and fat-free body mass. The development of body composition methodologies which more accurately measure the growth of muscle and bone as well as fat is a major challenge ahead. MH - Adipose Tissue/ANALYSIS ; Adolescence ; Adult ; *Body Composition ; Body Water/ANALYSIS ; Body Weight ; Bone and Bones/ANALYSIS ; Child ; Densitometry/METHODS ; Female ; *Growth ; Human ; Infant ; Male ; Minerals/ANALYSIS ; Obesity/*DIAGNOSIS ; Potassium/ANALYSIS ; Proteins/ ANALYSIS ; Reference Values ; Review ; Skinfold Thickness ; Sports SO - Exerc Sport Sci Rev 1986;14:325-57 7 UI - 86255818 AU - Ponce-Hornos JE ; Villamil MF TI - Sodium compartmentalization of the arterial wall revisited: ouabain, temperature and enzymatic effects. AB - The sodium (Na) fractions of the dog carotid artery were identified by analyzing the effects of different procedures on 24Na washout curves. Although these never yielded more than three exponential terms, four Na fractions were identified. The fast-exchanging component amounted to 73 mmoles Na/kg w.wt., followed the kinetics of diffusion in a flat sheet with a diffusion coefficient of 6.9 X 10(-6) cm2 X s-1, and remained unaltered under the different experimental conditions. The intermediate component exchanged with a half time (t0.5) of 5.3 min and amounted to 18 mmoles Na/kg w.wt. About one third of this (6 mmoles) was constituted by cellular Na and the remaining by non-cellular Na, probably associated with extracellular structures. These two fractions could be discriminated by: (a) decreasing the rate of exchange of the cellular fraction with ouabain or low temperature (17 degrees C); (b) cell damage by freezing and thawing combined with metabolic poisoning; (c) enzymatic digestion of extracellular structures. When procedures (a) and (c) were combined, the intermediate component entirely disappeared. A third residual component amounted to 0.6 mmoles Na/kg w.wt and exchanged with a t0.5 of 70 min. It was unaffected by cellular damage or enzymatic digestion and was masked by the cellular phase in effluxes conducted at 17 degrees C or under ouabain. Its size decreased by microscopic dissection of the dense adventitia, which is probably its source. MH - Animal ; Arteries/*METABOLISM/ULTRASTRUCTURE ; Body Fluid Compartments ; Carotid Arteries/METABOLISM ; Cold ; Dissection ; Dogs ; Hydrolases/ PHARMACODYNAMICS ; In Vitro ; Kinetics ; Ouabain/PHARMACODYNAMICS ; Potassium/METABOLISM ; Sodium/*METABOLISM ; Support, Non-U.S. Gov't SO - Methods Find Exp Clin Pharmacol 1986 Apr;8(4):213-21 8 UI - 86248827 AU - Cooper JC ; Laughland A ; Gunning EJ ; Burkinshaw L ; Williams NS TI - Body composition in ileostomy patients with and without ileal resection. AB - Body composition was measured in 24 patients who had previously undergone proctocolectomy and ileostomy. One group (control group) had undergone resection of only small amounts of terminal ileum (median 4 cm), the other group of patients (resected group) had undergone resection of greater lengths of small bowel (median 54 cm). These values of body composition were then compared with predicted values in normal subjects. Proctocolectomy and ileostomy without ileal resection did not significantly affect body weight, or the body contents of fat or water, but led to a reduction in total body nitrogen and total body potassium, suggesting a reduction in fat free mass. A modest resection of the terminal ileum undertaken during the course of proctocolectomy decreased body weight largely because of a reduction in body fat. None of the ileostomy patients was found to be dehydrated. MH - Adult ; Blood Chemical Analysis ; *Body Composition ; Body Water/ANALYSIS ; Diet ; Female ; Human ; *Ileostomy ; Ileum/*SURGERY ; Lipids/ANALYSIS ; Male ; Middle Age ; Nitrogen/ANALYSIS ; Potassium/ANALYSIS ; Support, Non-U.S. Gov't SO - Gut 1986 Jun;27(6):680-5 9 UI - 86244223 AU - Harbut RE ; Johanson CE TI - Third ventricle choroid plexus function and its response to acute perturbations in plasma chemistry. AB - The homeostatic role of the third ventricle choroid plexus (3VCP) in the maintenance of CSF electrolytes was investigated by quantifying alterations in CP epithelial ion concentrations induced by chemical perturbations of plasma in adult Sprague-Dawley rats. Significant regional differences (third vs fourth (4VCP) and lateral ventricle CP (LVCP] were found in epithelial content of Na+ and K+, with respect to baseline levels as well as alterations caused by 5-60 min of systemic metabolic acidosis. 3VCP, which comprises ca. 10% of total choroidal tissue, has a water content, extracellular fluid volume and vascularity comparable to 4VCP and LVCP; yet 3VCP is characterized by relatively high and low values for cellular [Na+] (68 mM) and [K+] (118 mM). Compared to time-matched controls, acute metabolic acidosis (i.p. NH4Cl) effected a response, i.e. increases [K+] and decreases [Na+], in 3VCP that was less than in 4VCP, and substantially smaller than in LVCP. The onset and duration of induced electrolyte changes were qualitatively similar among the 3 plexus regions. Although systemic acidosis severely altered CP electrolyte concentrations, it did not compromise CSF homeostasis of [K+] and [Na+]. The function of 3VCP is discussed in terms of secretory capacity, embryological origin, and innervation. Overall, the findings indicate that transport/permeability phenomena which mediate transmembrane distribution of Na+ and K+ in 3VCP differ quantitatively from other regions of the blood-CSF barrier. MH - Acidosis/CHEMICALLY INDUCED/PHYSIOPATHOLOGY ; Animal ; Biological Transport, Active ; *Blood-Brain Barrier ; Body Fluid Compartments ; Choroid Plexus/ANALYSIS/METABOLISM/*PHYSIOLOGY ; Comparative Study ; Organ Weight ; Potassium/*METABOLISM ; Rats ; Rats, Inbred Strains ; Sodium/*METABOLISM ; Support, U.S. Gov't, P.H.S. ; Time Factors SO - Brain Res 1986 May 21;374(1):137-46 10 UI - 86239715 AU - Dunson WA ; Heatwole H TI - Effect of relative shell size in turtles on water and electrolyte composition. AB - Interspecific differences in water, sodium, and potassium concentrations of entire freshwater turtles are related to the relative size of the shell. Species with proportionately smaller shells have higher water and potassium concentrations but lower sodium concentrations (expressed as mumol/g wet mass). These effects are associated with variation in the amount of shell bone, which is lower in water and potassium concentrations than other tissues. Within a single species there are also differences in composition related to total wet mass and relative shell mass. Smaller turtles have a relatively larger overall water concentration, a lower overall sodium concentration (expressed as mumol/g wet mass), and a larger relative wet mass of shell (expressed as % total wet mass). The shell in small turtles is lower in relative dry mass, higher in water concentration, and lower in sodium concentration (expressed as mumol/g wet mass) than in large turtles. There is also a striking inverse size-related difference in the proportion of overall sodium that is exchangeable. This is due to a decrease in the proportion of exchangeable sodium in the shell of larger turtles, perhaps related to progressive calcification. The magnitude of the effects of size and/or age on water and electrolyte composition of turtles has not been previously recognized but must now be taken into account before any interspecific or intraspecific comparisons in body composition are made. MH - Animal ; Body Composition ; Body Constitution ; Body Water/*METABOLISM ; Potassium/*METABOLISM ; Sodium/*METABOLISM ; Support, Non-U.S. Gov't ; Support, U.S. Gov't, Non-P.H.S. ; Turtles/ANATOMY & HISTOLOGY/*METABOLISM ; Water-Electrolyte Balance SO - Am J Physiol 1986 Jun;250(6 Pt 2):R1133-7 11 UI - 86239621 AU - Sj:ostr:om L ; Kvist H ; Cederblad A ; Tyl:en U TI - Determination of total adipose tissue and body fat in women by computed tomography, 40K, and tritium. AB - The adipose tissue volumes of 12 women were determined by computed tomography (CT). Body weight ranged from 46 to 129 kg. Nine or twenty-two transsectional scans were examined with respect to the adipose tissue area. The total adipose tissue volume (ATCT22 or ATCT9) was calculated by assuming linear changes in the adipose tissue area between adjacent scans. Body fat (BF) was also calculated from total body potassium (BF40K), from total body water (BFTHO), and from both these determinations (BF40K + THO). Body mass index (BMI) was calculated by dividing body weight (BW) by height2 (H2). ATCT22, ATCT9, and BFK were more closely related to BW and BMI than were BFTHO and BF40K + THO. When ATCT was used as a standard, the optimal index of adiposity based on BW and H was in the range BW/H0.8 to BW/H1.2. From the CT and 40K measurements it was possible to deduce that the potassium content is 62 mmol/kg fat free mass and 73-75 mmol/kg lean body mass. The error of ATCT9 was 0.6%, while that of BF40K was at least three to four times larger. It is concluded that the CT-based AT determination is the most reproducible method so far available. The technique might turn out to be of great value in human energy balance experiments. MH - Adipose Tissue/*PATHOLOGY ; Adult ; *Body Composition ; Body Height ; Body Water ; Body Weight ; Comparative Study ; Female ; Human ; Middle Age ; Obesity/*PATHOLOGY ; Potassium Radioisotopes/DIAGNOSTIC USE ; Support, Non-U.S. Gov't ; Tomography, X-Ray Computed ; Tritium/DIAGNOSTIC USE SO - Am J Physiol 1986 Jun;250(6 Pt 1):E736-45 12 UI - 86056775 AU - Blendis LM ; Harrison JE ; Russell DM ; Miller C ; Taylor BR ; Greig PD ; Langer B TI - Effects of peritoneovenous shunting on body composition. AB - The effect of peritoneovenous shunting on body composition has been studied in 7 cirrhotic patients undergoing a successful shunt and 3 patients in whom the shunt was unsuccessful. In the 7 patients with functioning shunts, their weight had decreased by a mean of 9 kg (p less than 0.001) by 6 wk after initial diuresis, natriuresis, and kaliuresis, and was associated with a decrease in total body potassium (TBK) but not total body nitrogen (TBN). This resulted in a significant decrease in the TBK/TBN ratio from 2.12 +/- 0.74 to 1.66 +/- 0.20 (p less than 0.01). By a mean of 14 mo, in these 7 patients there was a significant increase in mean TBN (from 1.54 +/- 0.10 to 1.84 +/- 0.10, p less than 0.005) associated with an improvement in the mean nitrogen index (from 0.74 +/- 0.04 to 0.88 +/- 0.04, p less than 0.005). These changes were associated with a significant increase in nonalcoholic calories, a nonsignificant increase in protein consumption, and a positive nitrogen balance. After the initial kaliuresis, mean potassium balance remained constantly positive (+22.7 +/- 3.4 mmol/day), serum aldosterone levels normalized, and TBK increased. In contrast, 3 patients with failed peritoneovenous shunting continued to lose weight significantly despite the presence of ascites; TBN and nitrogen index also decreased. In conclusion, body composition studies appear to have confirmed the clinical observation that cirrhotic patients with massive ascites have depleted body protein which is gradually repleted only after successful shunting. In this situation TBK, long used as a measure of lean body mass, is less satisfactory than TBN and nitrogen index. This improvement in body protein appears to be explained by an increased dietary intake associated with improved nitrogen balance, but these changes are not found in patients in whom the shunt failed. MH - Adult ; *Body Composition ; Body Weight ; Caloric Intake ; Comparative Study ; Dietary Proteins/ADMINISTRATION & DOSAGE ; Human ; Liver Cirrhosis/METABOLISM/THERAPY ; Liver Cirrhosis, Alcoholic/METABOLISM/ THERAPY ; Male ; Middle Age ; Nitrogen/*METABOLISM ; *Peritoneovenous Shunt ; Potassium/*METABOLISM ; Time Factors ; Water-Electrolyte Balance SO - Gastroenterology 1986 Jan;90(1):127-34