Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.6.3.1 (Mg2+-ATPase)
 1,484 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Leucine-binding protein described in an earlier paper was examined to characterize the dynamic properties of the system. Leucine-binding protein assembles into a large protein polymer or complex (greater than 302,000 daltons). Colchicine reduces and Mg2+ increases the amount of polymer formed. Trypsin destroys the isolated polymer but RNAase and collagenase do not. Mg2+-ATPase activity is present in the polymer fraction. The formation of the large complex suggests a quickly adaptable structure capable of responding to ionic and environmental conditions.
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PMID:Aggregation of binding protein from rat nerve. 72 98

Hepatocyte couplets were isolated by collagenase perfusion from rat liver. Between adjacent cells, the bile canaliculus forms a closed space into which secretion occurs. As in intact liver, Mg2+-ATPase is localized at the canalicular lumen, the organic anion fluorescein is excreted, and secretion is modified by osmotic gradients. By passing a microelectrode through one cell into the canalicular vacuole, a transepithelial potential profile was obtained. In 27 cell couplets the steady-state intracellular (-26.3 +/- 5.3 mV) and intracanalicular (-5.9 +/- 3.3 mV) potentials were recorded at 37 degrees C with reference to the external medium. Input resistances were determined within the cell (86 +/- 23 M omega) and in the bile canalicular lumen (32 +/- 17 M omega) by passing current pulses through the microelectrode. These data define electrical driving forces for ion transport across the sinusoidal, canalicular, and paracellular barriers and indicate ion permeation across a leaky paracellular junctional pathway. These findings indicate that the isolated hepatocyte couplet is an effective model for electrophysiologic studies of bile secretory function.
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PMID:Isolated rat hepatocyte couplets: a primary secretory unit for electrophysiologic studies of bile secretory function. 614 46