Linked Life Data

163685

Source:http://linkedlifedata.com/resource/pubmed/id/163685

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1975-5-28
pubmed:abstractText
Homogenate and plasma membrane fractions of Morris hepatoma 5123tc (h) and rat liver were studied with regard to their relative basal activties of adenylate cyclase and to the comparative responsiveness of this enzyme to glucagon, sodium fluoride, epinephrine, prostaglandin E1, and insulin. The basal adenylate cyclase activities of the hepatoma fractions were found to be similar to those of liver at an adenosine 5'triphosphate concentration of 3.2 mM; if the substrate affinity (Km adenosine 5'-triphosphate) of the tumor enzyme is comparable to that of liver, these findings suggest that the reduced basal cyclic adenosine 3':5'-monophosphate levels found to occur in hepatoma 5123tc (h) probably are not due to a decreased basal rate of formation of this cyclic nucleotide. Glucagon (5.6 muM) significantly stimulated adenylate cyclase in both fractions of hepatoma and livers; however, the responsiveness of the tumor enzyme to this hormone was substantially lower than the responsiveness of liver for both homogenate and plasma membrane preparations; i.e., activities were enhanced 18-fold (relative to the basal activity)for liver homogenate compared with only a 6-fold increase for tumor. With the plasma membrane preparations, glucagon increased the activities 5- and 3.5-fold in liver and hepatoma, respectively. Sodium fluoride (10mM), in contrast to glucagon, increased the adenylate cyclase activity to approximately the same extent (about 10-fold) in the liver and hepatoma preparations. Epinephrine (100 muM) enhanced the liver and hepatoma homogenate activites 3- to 4-fold and the hepatoma plasma membrane activities 2-fold; however, the liver plasma membrane activites were not increased. Prostaglandin E1 (56.6 MUM) significantly increased adenylate cyclase activites of liver and hepatoma homogenates (i.e., 1.5- and 3-fold, respectively) but not of the plasma membrane preparations. Insulin (0.7 muM) did not significantly alter adenylate cyclase activities in any of the preparations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
596-600
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
Comparative adenylate cyclase activities in homogenate and plasma membrane fractions of Morris hepatoma 5123tc (h).
pubmed:publicationType
Journal Article