title: [Studies on absorption kinetics of scopoletin in rat stomachs and intestines].
abstract: OBJECTIVE
  To study absorption kinetics of scopoletin in rat stomachs and intestines.
  
  
  METHODS
  Rats was cannulated for in situ recirculation. UV and HPLC methods were used to determine the concentrations of phenolsulfonphthalein and scopoletin, respectively.
  
  
  RESULTS
  The absorption rates in rat stomachs at 2 h after administration was 76.31%; The absorption rates at colon, duodenum, ileum and jejunum were 46.25%, 40.54%, 38.21%, 32.77%, respectively. The absorption rate constant (Ka) at concentrations of 10.0144, 20.0288-40.0576 mg x L(-1) in intestine were 0.6434, 0.6137, 0.5970 h(-1), respectively. The Ka of scopoletin at pH of 6.0, 6.8 and 7.4 in intestine were 0.6217, 0.6033, 0.6137 h(-1), respectively.
  
  
  CONCLUSIONS
  The concentrations and pH values of scopoletin solution had no distinctive effect on the absorption kinetics. The absorption of scopoletin was a first-order process with passive diffusion mechanism. Scopoletin was well absorbed at stomachs and intestines in rats. Colon was the best absorption site of scopoletin, which suggest that a sustained-release preparation should be suitable for this compound.
authors.affiliation: College of Traditional Chinese Medicine, China Pharmaceutical University, Nanjing 210038, China. yfxiacpu@126.com
authors.forename: Yu-feng
authors.initials: YF
authors.lastname: Xia
authors.forename: Yue
authors.initials: Y
authors.lastname: Dai
authors.forename: Qing-yu
authors.initials: QY
authors.lastname: Meng
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.forename: Ling-ling
authors.initials: LL
authors.lastname: Qiu
mesh_terms: D000042:Absorption; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D005260:Female; D005753:Gastric Mucosa / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012603:Scopoletin / Q000493:pharmacokinetics*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D012603:Scopoletin