Devazepide reversed effect of sincalide against morphine on rat jejunal activities.
OBJECTIVE
To study the antagonism of sincalide to the effect of morphine and its mechanism.


METHODS
The electrophysiologic and mechanic activities of rat jejunum in vitro were recorded.


RESULTS
Acetylcholine (ACh, 150 nmol.L-1) increased the spike potential amplitude (SPA) and the number (SPN) of rat jejunum in vitro, followed by an increase of jejunal contraction amplitudes (CA), showing a positive correlation. Morphine 330 nmol.L-1 inhibited the potentiation of ACh, showing a negative correlation. Sincalide 0.7 nmol.L-1 antagonized the effects of morphine, i.e., the SPA and SPN were increased again, followed by an increase of CA. CCK-A receptor antagonist devazepide (10 nmol.L-1) reversed the antagonism of sincalide to the effect of morphine.


CONCLUSIONS
Sincalide antagonized the effect of morphine which inhibited the potentiation of ACh on jejunal activities in vitro. The antagonistic effect of sincalide on morphine was mainly mediated by CCK-A receptor.
Xu
M Y
MY
Department of Physiology, Harbin Medical University, China.
Yang
X P
XP
Jin
H B
HB
Yang
C X
CX
Yang
L Z
LZ
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D020109:Devazepide / Q000494:pharmacology*; D015259:Dopamine Agents / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D007583:Jejunum / Q000502:physiology*; D008297:Male; D009020:Morphine / Q000037:antagonists & inhibitors*; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D011949:Receptors, Cholecystokinin / Q000037:antagonists & inhibitors; D012844:Sincalide / Q000494:pharmacology*
D015259:Dopamine Agents; D011949:Receptors, Cholecystokinin; D009020:Morphine; D020109:Devazepide; D012844:Sincalide