Adorno, Theodor (1903–1969)

Antagonism of the Gut-Contracting Effects of Bombesin and Neurotensin by Opioid Peptides, Morphine, Atropine or Tetrodotoxin

“…Atropine, too, made both neuro tensin and bombesin distinguishable from caer ulein: against tire former peptides it acted as a non-competitive antagonist, but against the latter as a dual antagonist. Another difference to caerulein (but not to CCK-8) was revealed by TTX which acted against this peptide in a surmountable way (Zetler, 1979), i.e., as a metactoid antagonist influencing an agonist sys tem with a receptor reserve ( Van den Brink, 1969). Obviously, tire indirect (postganglionic) gut-contracting action of peptides may have more than one mechanism of action.…”