Regional and molecular separation of the four bioactivities of 'tribulin'

Neurosci Lett. 1998 Jan 2;240(1):29-32. doi: 10.1016/s0304-3940(97)00916-6.

Abstract

The endocoid tribulin has four known bioactivities: monoamine oxidase A and B inhibitory activities (MAO-AI and MAO-BI) and peripheral and central benzodiazepine receptor binding inhibitory activities (PBR-I and CBR-I). Analysis of the four bioactivities in rat tissue reveals regional dissociation. Most notably liver was particularly rich in PBR-I yet contained no detectable MAO-AI. In addition we have succeeded in separating the four activities from human urine. MAO-AI and MAO-BI have greater retention on charcoal than PBR-I and CBR-I when eluted step-wise with aqueous methanol. MAO-AI can be separated from MAO-BI and in addition PBR-I can be separated from CBR-I by step aqueous methanol elution from Amberlite XAD-4. Hence we present two lines of evidence that, contrary to the original view, tribulin is composed of a number of distinct molecular components.

MeSH terms

  • Adrenal Glands / enzymology
  • Adrenal Glands / metabolism
  • Animals
  • Female
  • GABA-A Receptor Antagonists
  • Humans
  • Intestine, Large / enzymology
  • Intestine, Large / metabolism
  • Isatin*
  • Liver / enzymology
  • Liver / metabolism
  • Male
  • Monoamine Oxidase Inhibitors / isolation & purification
  • Monoamine Oxidase Inhibitors / metabolism*
  • Monoamine Oxidase Inhibitors / urine
  • Organ Specificity
  • Rats
  • Rats, Wistar
  • Receptors, GABA-A / metabolism
  • Spleen / enzymology
  • Spleen / metabolism

Substances

  • GABA-A Receptor Antagonists
  • Monoamine Oxidase Inhibitors
  • Receptors, GABA-A
  • Isatin
  • tribulin