title: [Changes in the activity of platelet L-arginine/nitric oxide pathway in hypercholesterolemia patients].
abstract: OBJECTIVE
  To investigate the changes of the platelet L-arginine (L-Arg)/nitric oxide (NO) pathway in hypercholesterolemia patients.
  
  
  METHODS
  The platelet NO production in 21 hypercholesterolemia (HC) patients and 26 normal individuals was assayed by spectrum, the NOS activity and the transportation of L-Arg were determined by (3)H-labelled L-Arg.
  
  
  RESULTS
  The NO production in hypercholesterolemic platelets [(24.06 +/- 3.70) nmol/10(8) platelets] was decreased significantly as compared with normal controls [(28.39 +/- 4.45) nmol/10(8) platelets] (P < 0.01), and so did the NOS activity [(1.46 +/- 0.47) pmol/10(8) platelets] vs (1.81 +/- 0.50) pmol/10(8) platelets]. The transportation of L-Arg by hypercholesterolemia platelets also decreased significantly than that by normal controls. The Vmax in the former [(46.84 +/- 3.39) pmol x (10(7) platelets)(-1) x min(-1)] was significantly lower than that in the latter [(53.89 +/- 3.45) pmol x (10(7) platelets)(-1) x min(-1)]. There was no difference between the two groups in K(d) (P > 0.05).
  
  
  CONCLUSIONS
  The activity of the L-arg/NO pathway in hypercholesterolemia platelets is decreased significantly as compared with normal controls, implying that it is probably one of the reasons for the hyperactivity of hypercholesterolemia platelets.
authors.affiliation: Department of Hematology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University of Medical Sciences, Guangzhou 510120, China.
authors.forename: W
authors.initials: W
authors.lastname: Kou
authors.forename: S
authors.initials: S
authors.lastname: Yin
authors.forename: D
authors.initials: D
authors.lastname: Nie
authors.forename: L
authors.initials: L
authors.lastname: Ma
authors.forename: S
authors.initials: S
authors.lastname: Xie
authors.forename: Z
authors.initials: Z
authors.lastname: Li
authors.forename: J
authors.initials: J
authors.lastname: Feng
authors.forename: L
authors.initials: L
authors.lastname: Xu
mesh_terms: D000328:Adult; D000368:Aged; D001120:Arginine / Q000378:metabolism*; D001792:Blood Platelets / Q000201:enzymology / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism
chemical_list: D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase