Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1977-3-21
pubmed:abstractText
The effect of different doses of luteinizing hormone on activation of protein kinases, cyclic AMP and testosterone production was studied in purified rat testis Leydig-cell preparations in the presence of 3-isobutyl-1-methylxanthine (a phosphodiesterase inhibitor). In addition, the nature of the protein kinases present in these cells and other tissues was investigated. The following results were obtained. 1. With all the amounts of luteinizing hormone used (0.1-1000 ng/ml), both activation of protein kinase and stimulation of testosterone production were demonstrated. With the lowest amount of luteinizing hormone (0.1 ng/ml), an 8.4+/-0.9% (S.E.M.,n=6) stimulation of protein kinase activation occurred, increasing to 100% with 1000 ng/ml, compared with 3.2+/-1.0%(S.E.M.,n=7) and 100% stimulation of testosterone production with 0.1 and 100 ng/ml respectively. 2. With amounts of luteinizing hormone up to 1 ng/ml (which gave half-maximal stimulation of testosterone production) no detectable increases in net cyclic AMP production were obtained. With higher amounts of luteinizing hormone, cyclic AMP production increased, but maximal production was not reached with 1000 ng/ml. 3. Two isoenzymic forms of protein kinase were present in Leydig cells and seminiferous tubules; type I was eluted with 0.075 M-and type II with 0.22-0.25 m-NaCl from DEAE-cellulose columns. 4. The protein kinase activity was not affected by the presence of erythrocytes in the Leydig-cell preparation, but varied depending on the type of histone used as substrate (histone F2b greater than mixed greater than histone F1).
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-165513, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-166607, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-166986, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-171267, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-177108, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-180976, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4336415, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4348550, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4351309, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4353683, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4358028, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4358076, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4360898, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4362338, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4376948, http://linkedlifedata.com/resource/pubmed/commentcorrection/189752-4742150
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
160
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
439-46
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Correlation of protein kinase activation and testosterone production after stimulation of Leydig cells with luteinizing hormone.
pubmed:publicationType
Journal Article, In Vitro