Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.4.21.5 (
thrombin
)
33,306
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Tyrosine protein kinase
(
TPK
) activity in rabbit platelets after stimulation by phorbol myristate acetate (PMA) or
thrombin
was directly estimated by 32P incorporation from (gamma-32P)ATP (adenosine triphosphate) into synthetic peptide angiotensin II. By PMA-treatment a net increase of
TPK
activity was obtained, while
thrombin
acted on the
TPK
quickly but stimulation was limited within the range attained by the control after lengthy incubation. The responsive
TPK
to these stimulators was localized mainly in membrane but much less in cytosol. The specific activity of the particulate
TPK
was low in the sonicate of control ice cold platelets but increased about 6-fold when the platelets were incubated at 37 degrees C. On a brief contact of platelets with PMA at 37 degrees C the
TPK
was fully activated and reached a maximum value about 130% of the control. Determination of phosphotyrosine phosphatase in the stimulated platelet sonicate revealed that its participation in the above described increase of 32P-incorporation was meagre. The quick response suggested a possible role of
TPK
in the signal transduction through the platelet cell membrane.
...
PMID:Net increase of platelet membrane tyrosine specific-protein kinase activity by phorbol myristate acetate. 229 69
