Inverse relation between plasma inorganic phosphate and phospholipids in mice: effect of dietary inorganic phosphate, fasting and glucagon.
We measured in mice under various conditions plasma phospholipids (PlipPl), total phosphate (PtotPl), inorganic phosphate (PiPl), and calculated other phosphate-containing material (PXPl) by subtracting (Plip + Pi)Pl from PtotPl. In mice fed low Pi diet (LPD) for 10 days, PlipPl was higher, PxPl did not change, whereas PiPl and PtotPl were lower than under high Pi diet (HPD). A highly significant inverse correlation was found between PlipPl and PiPl. The effect on PlipPl of maneuvers known to change PiPl acutely (within hours) was then investigated. In LPD mice, 6 h fasting, which increases PiPl, led to a decrease of PlipPl without significant changes of PtotPl and PxPl. The conspicuous rise in PiPl observed with glucagon treatment was associated with a decrement of PlipPl of the same magnitude as the increase in PiPl without a change of PtotPl or PxPl. Finally, injection of Pi lowered PlipPl in a dose-dependent manner within 2 h. In mice fed HPD, PlipPl decreased similarly during all acute maneuvers described under LPD, except Pi injection, where it did not decrease. In conclusion, the effects described above would suggest that the regulation of the two phosphate species may be linked and that PlipPl may possibly be involved in Pi homeostasis.
Mühlbauer
R C
RC
Department of Pathophysiology, University of Berne, Switzerland.
Fleisch
H
H
D000818:Animals; D005215:Fasting; D005260:Female; D005934:Glucagon / Q000494:pharmacology*; D006706:Homeostasis / Q000187:drug effects; D051379:Mice; D008815:Mice, Inbred Strains; D010710:Phosphates / Q000097:blood*; D010743:Phospholipids / Q000097:blood*; D016226:Phosphorus, Dietary / Q000494:pharmacology*
D010710:Phosphates; D010743:Phospholipids; D016226:Phosphorus, Dietary; D005934:Glucagon