title: [Determination and comparison of plasma protein binding rate of alkaloids from seed of Strychnou nux-vomica].
abstract: OBJECTIVE
  To determine the plasma protein binding rates of brucine and strychnine in total alkaloids from the seed of Strychnou nux-vomica, and make comparison with the single components at the same concentration.
  
  
  METHODS
  Ultrafiltration was employed to determine the rat the plasma protein binding rate of the alkaloids from the seed of S. nux-vomica. The plasma concentrations were measured by RP-HPLC.
  
  
  RESULTS
  The protein binding rates of brucine were (65.60 3.01)%, (68.20 +/- 7.80)%, (59.58 +/- 3.78)% when the plasma concentrations was 0.520, 1.300, 2.600 mg x L(-1), respectively. The protein binding rates of strychnine was (66.17 +/- 6.36)%, (67.10 +/- 2.52)%, (57.21 +/- 0.79)% when the plasma concentrations were 0.936, 2.340, 4.680 mg x L(-1) respectively. As to the total alkaloids from the seed of S. nux-vomica, The protein binding rate of brucine was (62.19 +/- 2.45)%, (69.55 +/- 5.84)%, (61.76 +/- 3.68)% when the plasma concentrations were 0.519, 1.288, 2.607 mg x L(-1), respectively. And the protein binding rates of strychnine were (54.79 +/- 3.55)%, (57.13 +/- 4.49)%, (59.31 +/- 3.65)% when the plasma concentrations were 0.940, 2.338, 4.674 mg x L(-1), respectively.
  
  
  CONCLUSIONS
  Brucine and strychnine have medium capacity in binding to plasma protein. In comparison with the single component of the same concentration, the protein binding rate of brucine in total alkaloids shows little difference, while there seems to be an obvious decrease for strychnine.
authors.affiliation: College of Pharmnacy, Nanjing University of Chinese Medicine, Nanjing 210046, China. xuan_jeanne@163.com
authors.forename: Xuan
authors.initials: X
authors.lastname: Wang
authors.forename: Chaoqin
authors.initials: C
authors.lastname: He
authors.forename: Ya
authors.initials: Y
authors.lastname: Chen
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Baochang
authors.initials: B
authors.lastname: Cai
mesh_terms: D000470:Alkaloids / Q000032:analysis / Q000493:pharmacokinetics*; D000818:Animals; D001798:Blood Proteins / Q000737:chemistry / Q000378:metabolism*; D004365:Drugs, Chinese Herbal / Q000032:analysis / Q000493:pharmacokinetics*; D011485:Protein Binding; D051381:Rats; D017207:Rats, Sprague-Dawley; D012639:Seeds / Q000737:chemistry; D031451:Strychnos / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D001798:Blood Proteins; D004365:Drugs, Chinese Herbal