title: Intralenticular water interactions with phosphates in the intact crystalline lens.
abstract: Since the ATP molecule is associated with the intracellular milieu, which consists mainly of water, this study suggests an intimate intracellular association with water molecules. Intact canine crystalline lenses (n = 6) were incubated at 37 degrees C in a buffer containing a pure D2O solvent and examined by [31P]-nuclear magnetic resonance (NMR) spectroscopy. Control lenses (n = 6) from contralateral eyes were incubated in a pure H2O-based buffer. During the first 4 h of a 24-hour incubation, the D2O-incubated lens maintained its phosphorus metabolic profile, indicating that the tissue maintains its metabolic health. During this period, however, the spectral signal widths of ATP narrowed progressively. Spectral-simulation analysis of ATP alpha-, beta- and gamma-phosphate signals revealed that the gamma-phosphate signal was narrowed significantly in contrast to the alpha-phosphate signal. Such differential signal narrowing within a single NMR spectrum indicates that the principal intracellular site of water hydrogen binding to the ATP molecule is at the gamma-group phosphate.
authors.affiliation: Howe Laboratory of Ophthalmology, Harvard Medical School, Massachusetts Eye & Ear Infirmary, Boston.
authors.forename: T
authors.initials: T
authors.lastname: Glonek
authors.forename: J V
authors.initials: JV
authors.lastname: Greiner
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001834:Body Water / Q000378:metabolism*; D004285:Dogs; D007908:Lens, Crystalline / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D010710:Phosphates / Q000378:metabolism*
chemical_list: D010710:Phosphates; D000255:Adenosine Triphosphate