Potentiation of cholinergic activity with pyridino[1,2-a]imidazo[5,4-b]indole: in vitro studies.
1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction.
Maleque
M A
MA
Department of Pharmacology, Meharry Medical College, Nashville, TN 37208.
Adhikary
P K
PK
Pavuluri
S
S
Kopsombut
P
P
Rucker
H K
HK
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D002802:Cholinesterases / Q000097:blood; D003714:Denervation; D006168:Guinea Pigs; D007082:Ileum / Q000187:drug effects / Q000294:innervation; D007093:Imidazoles / Q000494:pharmacology*; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009045:Motor Endplate / Q000187:drug effects; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000294:innervation; D010275:Parasympathetic Nervous System / Q000187:drug effects*; D011725:Pyridines / Q000494:pharmacology*; D011894:Rana pipiens; D012584:Sciatic Nerve / Q000187:drug effects
D007093:Imidazoles; D007211:Indoles; D011725:Pyridines; C063990:pyridino(1,2-a)imidazo(5,4-b)indole; D002802:Cholinesterases; D000109:Acetylcholine