Pre- and postsynaptic components of nicotinic long-term potentiation in the superior cervical ganglion of the cat. 1994

M A Morales, and M Bachoo, and B Collier, and C Polosa
Department of Physiology, McGill University, Montreal, Quebec, Canada.

1. In anesthetized, atropine-treated cats we measured the acetylcholine (ACh) release into the venous effluent of the superior cervical ganglion (SCG) and the nictitating membrane (NM) contraction evoked by a 2-Hz, 20-s test train to the ipsilateral cervical sympathetic trunk (CST). We also measured NM contraction produced by injection of ACh (50 micrograms) or 1,1-dimethyl-4-phenylpiperazinium (DMPP, 5 micrograms) into the arterial supply of the ipsilateral SCG. 2. After a 10- to 30-s, 40-Hz conditioning train to CST these responses were all potentiated. The potentiation of the NM response evoked by the test train or by the exogenous agonists was long lasting (90% decay in 64 +/- 10 min, mean +/- SE, for the train-evoked response; 42 +/- 9 min for the response to injected ACh; 61 +/- 18 min for the response to injected DMPP), whereas the potentiation of the ACh release lasted only for 9 min. 3. On the assumption that ACh and DMPP injected into the ganglionic arterial supply acted postsynaptically, these data suggest that the main mechanism of the long-term potentiation (LTP) of nicotinic transmission in SCG is an increase in postsynaptic responsiveness. Because the response to KCl (250 micrograms) injected into the ganglionic arterial supply was not potentiated after the conditioning train, a posttrain increase in excitability of the postsynaptic membrane is not likely to be the cause of the postsynaptic increased responsiveness to ACh and DMPP.(ABSTRACT TRUNCATED AT 250 WORDS)

UI MeSH Term Description Entries
D008297 Male Males
D009435 Synaptic Transmission The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES. Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D011978 Receptors, Nicotinic One of the two major classes of cholinergic receptors. Nicotinic receptors were originally distinguished by their preference for NICOTINE over MUSCARINE. They are generally divided into muscle-type and neuronal-type (previously ganglionic) based on pharmacology, and subunit composition of the receptors. Nicotinic Acetylcholine Receptors,Nicotinic Receptors,Nicotinic Acetylcholine Receptor,Nicotinic Receptor,Acetylcholine Receptor, Nicotinic,Acetylcholine Receptors, Nicotinic,Receptor, Nicotinic,Receptor, Nicotinic Acetylcholine,Receptors, Nicotinic Acetylcholine
D001767 Blinking Brief closing of the eyelids by involuntary normal periodic closing, as a protective measure, or by voluntary action. Orbicularis Oculi Reflex,Reflex, Blink,Reflex, Corneal,Reflex, Orbicularis Oculi,Winking,Blink Reflexes,Corneal Reflexes,Orbicularis Oculi Reflexes,Blink Reflex,Reflexes, Blink,Reflexes, Orbicularis Oculi
D002415 Cats The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801) Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D005260 Female Females
D000109 Acetylcholine A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system. 2-(Acetyloxy)-N,N,N-trimethylethanaminium,Acetilcolina Cusi,Acetylcholine Bromide,Acetylcholine Chloride,Acetylcholine Fluoride,Acetylcholine Hydroxide,Acetylcholine Iodide,Acetylcholine L-Tartrate,Acetylcholine Perchlorate,Acetylcholine Picrate,Acetylcholine Picrate (1:1),Acetylcholine Sulfate (1:1),Bromoacetylcholine,Chloroacetylcholine,Miochol,Acetylcholine L Tartrate,Bromide, Acetylcholine,Cusi, Acetilcolina,Fluoride, Acetylcholine,Hydroxide, Acetylcholine,Iodide, Acetylcholine,L-Tartrate, Acetylcholine,Perchlorate, Acetylcholine
D000320 Adrenergic Fibers Nerve fibers liberating catecholamines at a synapse after an impulse. Sympathetic Fibers,Adrenergic Fiber,Fiber, Adrenergic,Fiber, Sympathetic,Fibers, Adrenergic,Fibers, Sympathetic,Sympathetic Fiber
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D013569 Synapses Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions. Synapse

Related Publications

M A Morales, and M Bachoo, and B Collier, and C Polosa
October 1988, The Journal of physiology,
M A Morales, and M Bachoo, and B Collier, and C Polosa
March 1991, Brain research,
M A Morales, and M Bachoo, and B Collier, and C Polosa
March 1982, Science (New York, N.Y.),
M A Morales, and M Bachoo, and B Collier, and C Polosa
May 1995, Journal of neurophysiology,
M A Morales, and M Bachoo, and B Collier, and C Polosa
April 1997, Brain research,
M A Morales, and M Bachoo, and B Collier, and C Polosa
January 1974, Naunyn-Schmiedeberg's archives of pharmacology,
M A Morales, and M Bachoo, and B Collier, and C Polosa
June 2002, Neuroscience research,
M A Morales, and M Bachoo, and B Collier, and C Polosa
June 1985, The Journal of physiology,
M A Morales, and M Bachoo, and B Collier, and C Polosa
March 1991, Journal of neurophysiology,
Copied contents to your clipboard!