Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)
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Proc. Soc. Exp. Biol. Med. · Apr 1989
Phospholipid changes during adaptation to acidosis in urinary bladder of Bufo marinus.
The purpose of this study was to determine whether phospholipids (PL) play a role in the adaptation to metabolic acidosis by toad urinary bladder epithelium. Toads were placed in an NH4Cl acidosis for 48 hr. Quarter bladders were removed and incubated with [32P]orthophosphate or [3H]arachidonic acid for 1 hr at 25 degrees C. ⋯ Fractional PL (reported as percentage of fraction of total PL based on total lipid phosphorus) analysis in normal toads revealed phosphatidylinositol = 8.1 +/- 0.6% and PE = 27 +/- 1.2%, whereas for acidotic toads phosphatidylinositol = 11 +/- 0.6% and PE = 32 +/- 1.0% (P less than 0.01 for both). Aldosterone, a known stimulator of acidification, had no effect on 32P incorporation into PL fractions of the bladder. The increase in PL turnover following induction of acidosis is consistent with increased membrane synthesis or turnover during metabolic acidosis and this may reflect an increased transport of vesicular H+-ATPase into the apical membrane or the result of a proliferation of acid-secreting mitochondria-rich cells or both.