Lipoprotein receptor 'CK'--dependent signalling in human platelets.
The study addressed to understand whether or not lipoproteins at low concentrations could modulate Receptor-'C' dependent platelet signalling revealed that LDL, like exogenous cholesterol, had the capacity to initiate PLD-dependent platelet signalling in a dose dependent fashion and this effect was inhibited in presence of HDL; cAMP; DTT; Zn++ and butanol whereas cGMP had no effect upon this PLD-dependent signalling. Further Receptor 'C' from platelet in the purified-form displayed LDL-or cholesterol-dependent autophosphorylation at the tyrosine residues and this Receptor-'C' tyrosine kinase (Receptor-Ck) activity contributed to the observed LDL-or cholesterol -dependent PLD activity in human platelets. Based upon these results coupled with earlier results, an attempt was made to define the lipoprotein-dependent platelet signalling pathway.
Kaul
D
D
Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Kochhar
N
N
Singh
J
J
D000255:Adenosine Triphosphate / Q000494:pharmacology; D001792:Blood Platelets / Q000378:metabolism*; D002784:Cholesterol / Q000494:pharmacology; D008078:Cholesterol, LDL / Q000378:metabolism; D006801:Humans; D008075:Lipoproteins, HDL / Q000494:pharmacology; D008077:Lipoproteins, LDL / Q000494:pharmacology; D010739:Phospholipase D / Q000378:metabolism; D010766:Phosphorylation; D020794:Receptor Protein-Tyrosine Kinases / Q000378:metabolism*; D018110:Receptors, Lipoprotein / Q000378:metabolism*; D015398:Signal Transduction; D014443:Tyrosine / Q000494:pharmacology
D008078:Cholesterol, LDL; D008075:Lipoproteins, HDL; D008077:Lipoproteins, LDL; D018110:Receptors, Lipoprotein; D014443:Tyrosine; D000255:Adenosine Triphosphate; D002784:Cholesterol; D020794:Receptor Protein-Tyrosine Kinases; D010739:Phospholipase D