title: K+, Na+, Mg2+, Ca2+, and water contents in human skeletal muscle: correlations among these monovalent and divalent cations and their alterations in K+ -depleted subjects.
abstract: None of previous studies had simultaneously analyzed the K(+), Na(+), Mg(2+), and Ca(2+) contents in human skeletal muscle. We examined extensively and simultaneously the levels of all these cations and examined water content in vastus lateralis and pectoralis major muscles in 30 northeastern Thai men who were apparently healthy but died from an accident. Specimen collection was performed within 6 h of death. We used atomic absorption or flame photometry to measure the level of muscle cation. Histopathology of muscle and kidney was also evaluated. K(+), Na(+), Mg(2+), and Ca(2+) contents in vastus lateralis were 84.74 +/- 1.50, 38.64 +/- 0.77, 7.58 +/- 0.17, and 0.94 +/- 0.06 micromol/g wet weight, respectively, whereas K(+), Na(+), and Mg(2+) contents in pectoralis major were 82.83 +/- 1.54, 37.57 +/- 0.72, and 7.30 +/- 0.17 micromol/g wet weight, respectively. The water component was comparable in vastus lateralis and pectoralis major (78.66 +/- 0.41 and 78.09 +/- 0.56 %, respectively). Based on muscle K(+) levels, we divided the subjects into 2 main groups: K(+)-depleted (KD) group (K(+) < 80 micromol/g wet weight; n = 7) and non-K(+)-depleted (NKD) group (K(+) > or = 80 micromol/g wet weight; n = 23). In the KD muscle, Na(+) and Ca(2+) levels were significantly higher, whereas the level of Mg(2+) was significantly lower. Linear regression analysis showed significant correlations of K(+) and Mg(2+) levels and between Na(+) and Ca(2+). However, K(+) and Mg(2+) had the negative correlation with Na(+) and Ca(2+). Histopathologic examination showed no change in the KD muscles, whereas 29% (2 of 7) of the KD kidneys had vacuolization in proximal renal tubular cells. Our study not only provided the descriptive data but also implied the balance or homeostasis of these monovalent and divalent cations in their muscle pools.
authors.affiliation: Department of Biochemistry, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Ratree
authors.initials: R
authors.lastname: Tavichakorntrakool
authors.forename: Vitoon
authors.initials: V
authors.lastname: Prasongwattana
authors.forename: Pote
authors.initials: P
authors.lastname: Sriboonlue
authors.forename: Anucha
authors.initials: A
authors.lastname: Puapairoj
authors.forename: Chaisiri
authors.initials: C
authors.lastname: Wongkham
authors.forename: Thitichai
authors.initials: T
authors.lastname: Wiangsimma
authors.forename: Wattana
authors.initials: W
authors.lastname: Khunkitti
authors.forename: Sombat
authors.initials: S
authors.lastname: Triamjangarun
authors.forename: Maneewan
authors.initials: M
authors.lastname: Tanratanauijit
authors.forename: Amporn
authors.initials: A
authors.lastname: Chamsuwan
authors.forename: Wirut
authors.initials: W
authors.lastname: Khunkitti
authors.forename: Pa-Thai
authors.initials: PT
authors.lastname: Yenchitsomanus
authors.forename: Visith
authors.initials: V
authors.lastname: Thongboonkerd
mesh_terms: D000059:Accidents; D001834:Body Water / Q000378:metabolism*; D002102:Cadaver; D002118:Calcium / Q000032:analysis; D002413:Cations, Divalent / Q000032:analysis*; D002414:Cations, Monovalent / Q000032:analysis*; D006706:Homeostasis; D006801:Humans; D007668:Kidney / Q000473:pathology; D008274:Magnesium / Q000032:analysis; D008275:Magnesium Deficiency / Q000378:metabolism / Q000473:pathology; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D011188:Potassium / Q000032:analysis*; D011191:Potassium Deficiency / Q000378:metabolism / Q000473:pathology; D012016:Reference Values; D012044:Regression Analysis; D012964:Sodium / Q000032:analysis; D013785:Thailand; D014020:Tissue Extracts / Q000032:analysis
chemical_list: D002413:Cations, Divalent; D002414:Cations, Monovalent; D014020:Tissue Extracts; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium