NMR characteristics of intracellular K in the rat salivary gland: a 39K NMR study using double-quantum filtering.
Intracellular K of the perfused rat mandibular salivary gland was measured by 39K NMR spectroscopy at 8.45 T. Multiple-quantum NMR arising from multiple-exponential decay was used to eliminate the resonance due to extracellular K in the perfused gland at 25 degrees C. The resonance due to intracellular K consisted of two Lorentzian signals stemming from the [spin 1/2 to -1/2] coherence (sharp resonance) and the [spin -1/2 to -3/2], [spin 3/2 to 1/2] coherences (broad resonance). The transverse relaxation time (T2) corresponding to the [spin 1/2 to -1/2] coherence was ca. 2.5 ms, and that corresponding to the [spin -1/2 to -3/2], [spin 3/2 to 1/2] coherences was ca. 0.4 ms. The relaxation time of the double-quantum coherence of rank 3 (originating from product operators like Ix2Iz) was determined to be ca. 0.2 ms. These results suggest the possibility of the presence of a single homogeneous population of intracellular K with a correlation time of ca. 2.5 x 10(-8) s and a quadrupolar coupling constant of ca. 1.4 MHz.
Seo
Y
Y
Department of Molecular Physiology, National Institute for Physiological Sciences, Okazaki, Japan.
Murakami
M
M
Suzuki
E
E
Kuki
S
S
Nagayama
K
K
Watari
H
H
D000818:Animals; D005374:Filtration / Q000295:instrumentation; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008334:Mandible; D010477:Perfusion; D011188:Potassium / Q000032:analysis*; D011789:Quantum Theory; D051381:Rats; D012469:Salivary Glands / Q000032:analysis*
D011188:Potassium