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1. Acetylcholine (ACh) is important as the transmitter responsible for neuromuscular transmission. Here we report the non-quantal release of ACh from embryonic myocytes. 2. Co-cultures of spinal neurons and myotomal muscle cells were prepared from 1-day-old Xenopus embryos. Single channel currents were recorded in the non-innervated myocytes. When the patch pipette was filled with Ringer solution alone, spontaneous single channel currents occurred, which were inhibited by d-tubocurarine (d-Tc). 3. The channel conductance appearing in Ringer solution (37.3 pS) was similar to that of an embryonic-type ACh channel (36.9 pS), indicating that ACh is probably released from myocytes in normal Ringer solution. 4. When the patch pipette was filled with anticholinesterase alone to prevent hydrolysis of ACh released from myocytes, both physostigmine and neostigmine in a concentration-dependent manner increased channel open probability; it was reduced by d-Tc or alpha-bungarotoxin. 5. Vesamicol and quinacrine, vesicular transporter inhibitors, reduced the channel open probability caused by ACh released from myocytes in the presence of neostigmine or physostigmine. 6. Intracellular alkalinization with NH4Cl inhibited the ACh release from myocytes, whereas, extracellular alkalinization, brought about by replacing normal Ringer solution, with pH 8.6 Ringer solution enhanced ACh release. 7. The immunocytochemistry of choline acetyltransferase (ChAT) showed that ChAT exists in both myocytes and neuronal cells but not in fibroblasts. 8. These results suggest that embryonic myocytes are capable of synthesizing and releasing ACh in a non-quantal manner. Extracellular alkalinization enhanced and intracellular alkalinization inhibited ACh release from myocytes.
Anderson,
Proton gradient linkage to active uptake of [3H]acetylcholine by Torpedo electric organ synaptic vesicles.
1982, Pubmed
Anderson,
Proton gradient linkage to active uptake of [3H]acetylcholine by Torpedo electric organ synaptic vesicles.
1982,
Pubmed Anderson,
Inhibition of [3H]acetylcholine active transport by tetraphenylborate and other anions.
1983,
Pubmed Anderson,
Pharmacological characterization of the acetylcholine transport system in purified Torpedo electric organ synaptic vesicles.
1983,
Pubmed Balice-Gordon,
In vivo observations of pre- and postsynaptic changes during the transition from multiple to single innervation at developing neuromuscular junctions.
1993,
Pubmed Bray,
Evidence for the role of non-quantal acetylcholine in the maintenance of the membrane potential of rat skeletal muscle.
1982,
Pubmed Ceccarelli,
Vesicle hypothesis of the release of quanta of acetylcholine.
1980,
Pubmed Dan,
Quantal transmitter secretion from myocytes loaded with acetylcholine.
1992,
Pubmed
,
Xenbase Dan,
Retrograde interactions during formation and elimination of neuromuscular synapses.
1994,
Pubmed Decker,
Calcium permeability of the nicotinic acetylcholine receptor: the single-channel calcium influx is significant.
1990,
Pubmed Dolezal,
The synthesis and release of acetylcholine in normal and denervated rat diaphragms during incubation in vitro.
1983,
Pubmed Drachman,
Neurotrophic regulation of two properties of skeletal muscle by impulse-dependent and spontaneous acetylcholine transmission.
1982,
Pubmed Edwards,
Is an acetylcholine transport system responsible for nonquantal release of acetylcholine at the rodent myoneural junction?
1985,
Pubmed Fu,
Potentiation by endogenously released ATP of spontaneous transmitter secretion at developing neuromuscular synapses in Xenopus cell cultures.
1994,
Pubmed
,
Xenbase Fu,
Regulation of acetylcholine release by presynaptic nicotinic receptors at developing neuromuscular synapses.
1997,
Pubmed
,
Xenbase Fu,
Regulatory role of ATP at developing neuromuscular junctions.
1995,
Pubmed
,
Xenbase Grosman,
The human choline acetyltransferase gene encodes two proteins.
1995,
Pubmed Hamill,
Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches.
1981,
Pubmed Hsu,
Use of avidin-biotin-peroxidase complex (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled antibody (PAP) procedures.
1981,
Pubmed Katz,
Transmitter leakage from motor nerve endings.
1977,
Pubmed Katz,
Does the motor nerve impulse evoke 'non-quantal' transmitter release?
1981,
Pubmed Kidokoro,
Distribution and density of alpha-bungarotoxin binding sites on innervated and noninnervated Xenopus muscle cells in culture.
1982,
Pubmed
,
Xenbase Laufer,
Activity-dependent regulation of gene expression in muscle and neuronal cells.
1989,
Pubmed Liou,
Regulation of quantal secretion from developing motoneurons by postsynaptic activity-dependent release of NT-3.
1997,
Pubmed
,
Xenbase Lo,
Heterosynaptic suppression of developing neuromuscular synapses in culture.
1994,
Pubmed
,
Xenbase Mathers,
Studies on neurotrophic regulation of murine skeletal muscle.
1978,
Pubmed Miledi,
Neural and non-neural acetylcholine in the rat diaphragm.
1982,
Pubmed Rink,
Cytoplasmic pH and free Mg2+ in lymphocytes.
1982,
Pubmed Roos,
Intracellular pH.
1981,
Pubmed Tucek,
The synthesis of acetylcholine in skeletal muscles of the rat.
1982,
Pubmed Usdin,
Molecular biology of the vesicular ACh transporter.
1995,
Pubmed Vyskocil,
Inhibition of non-quantal acetylcholine leakage by 2(4-phenylpiperidine)cyclohexanol in the mouse diaphragm.
1985,
Pubmed Wu,
DIDS-sensitive pHi regulation in single rat cardiac myocytes in nominally HCO3-free conditions.
1994,
Pubmed Zheng,
Turning of nerve growth cones induced by neurotransmitters.
1994,
Pubmed
,
Xenbase
