title: Fluctuation in the intracellular concentration of Na+ and Cl- but not of K+ or Mg2+ at mitosis of the first cell cycle in fertilized sea urchin eggs.
abstract: This report concerns changes in the cytoplasmic concentration of Na+, Cl-, K+ and Mg2+ during the first cell cycle and into the second cell cycle of fertilized sea urchin eggs of Lytechinus variegatus. The results of electron probe x-ray microanalysis showed a significant equimolar decrease in Na+ and Cl- at the first cell division which was followed by a significant increase early in the second cell cycle. Neither K+ nor Mg2+ showed such significant changes. The loss of a large fraction of the Na+ ions from the egg at metaphase was not accompanied by a significant egg volume change. The observed pattern of ionic change was related to several previously reported chemical and metabolic changes at cell division in sea urchin eggs.
authors.affiliation: Department of Cellular and Structural Biology, University of Texas Health Science Center, San Antonio 78284.
authors.forename: I L
authors.initials: IL
authors.lastname: Cameron
authors.forename: K E
authors.initials: KE
authors.lastname: Hunter
authors.forename: N K
authors.initials: NK
authors.lastname: Smith
mesh_terms: D000818:Animals; D002712:Chlorides / Q000378:metabolism*; D004577:Electron Probe Microanalysis; D008274:Magnesium / Q000378:metabolism*; D008938:Mitosis; D010063:Ovum / Q000166:cytology / Q000378:metabolism; D011188:Potassium / Q000378:metabolism*; D012617:Sea Urchins / Q000166:cytology / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*
chemical_list: D002712:Chlorides; D012964:Sodium; D008274:Magnesium; D011188:Potassium