Serum protein binding of penbutolol in patients with hepatic cirrhosis.
Serum protein binding of penbutolol, a non-cardioselective beta-blocker agent of basic nature, has been studied in healthy subjects and in patients with hepatic cirrhosis. The percentage of free penbutolol in serum containing 200 ng/ml was markedly increased in patients with hepatic cirrhosis, when compared with the group of healthy volunteers (8.17 +/- 1.13% in patients vs 3.41 +/- 0.19 in control). No significant differences in the levels of serum alpha-acid-glycoprotein (the major protein implicated in the serum binding of penbutolol) were detected. Differences in the overall affinity constant for the binding were apparent between both groups (nKa = 5.28 X 10(5) M-1 in patients vs 12.03 X 10(5) M-1 in healthy volunteers). These results suggest a qualitative change in alpha-acid-glycoprotein molecule, from hepatic patients, but further studies are needed to clarify this point.
Aguirre
C
C
Department of Pharmacology, Faculty of Medicine, University of Pais Vasco, Vizcaya, Spain.
Calvo
R
R
Rodríguez Sasiaín
J M
JM
D000328:Adult; D000368:Aged; D001798:Blood Proteins / Q000378:metabolism*; D005260:Female; D006801:Humans; D008103:Liver Cirrhosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010394:Penbutolol / Q000378:metabolism*; D011412:Propanolamines / Q000378:metabolism*; D011485:Protein Binding
D001798:Blood Proteins; D011412:Propanolamines; D010394:Penbutolol