Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
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Drug
Enzyme
Compound
Query: EC:3.6.3.1 (
Mg2+-ATPase
)
1,484
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A high affinity Ca2+-stimulated, Mg2+-dependent ATPase (Ca2+-
Mg2+-ATPase
) was identified in microsomes and plasma membrane vesicles isolated from rat hepatocytes. The distribution of this enzyme was similar to that of the plasma membrane marker enzymes alkaline phosphodiesterase and 5'-nucleotidase. The Ca2+-
Mg2+-ATPase
had an apparent half-saturation constant of approximately 75 nM for Ca2+. After incubation of rat hepatocytes with 25 nM
vasopressin
for 3 min, the activity of Ca2+-
Mg2+-ATPase
was decreased 15-30%. The effect of
vasopressin
on the activity of this enzyme was near maximal after incubating hepatocytes with
vasopressin
for only 15 sec. The concentration of
vasopressin
needed for half-maximal inhibition of this enzyme in hepatocytes was approximately 6 nM. Treatment of the hepatocytes with 10 microM phenylephrine caused about a 10% decrease in ATPase activity while 10 nM glucagon or 200 microU/ml insulin did not affect the enzyme. These findings suggest that inhibition of the Ca2+-
Mg2+-ATPase
activity may be part of the mechanism by which
vasopressin
and alpha-adrenergic agonists elevate cytosolic Ca2+ in hepatocytes.
...
PMID:Regulation of Ca2+-Mg2+-ATPase activity in hepatocyte plasma membranes by vasopressin and phenylephrine. 613 76
