Number of acetylcholine receptors per end plate

Value 3e+7 receptors/end plate
Organism Mouse Mus musculus
Reference Krnjević, K. "Chemical nature of synaptic transmission in vertebrates." Physiological Reviews pp.418-540 :(1974) 54.2 p.427 2nd paragraph
Primary Source [66] Barnard EA, Wieckowski J, Chiu TH. Cholinergic receptor molecules and cholinesterase molecules at mouse skeletal muscle junctions. Nature. 1971 Nov 26 234(5326):207-9. [1005] Porter CW, Chiu TH, Wieckowski J, Barnard EA. Types and locations of cholinergic receptor-like molecules in muscle fibres. Nat New Biol. 1973 Jan 3 241(105):3-7.PubMed ID4943086, 4512330
Method Primary source [1005] p.3 left column bottom paragraph: "Ultrastructural Location of Ach-receptors: Mice were injected intravenously with a lethal dose (1.5µg/g body weight) of 3H-α-bungarotoxin, and at death the diaphragm was removed and fixed (2h, 0˚C) in 3% glutaraldehyde, pH 7.4. Endplate-rich areas were dissected out and sections prepared for electron microscope autoradiography. All end-plates observed were labelled, while the labelling of muscle outside the endplates was negligible (Fig. 1)."
Comments P.427 2nd paragraph: "The junction seems to be constructed remarkably efficiently for the maximal utilization of any released ACh (AcetylCholine). The high density of receptors [3×10^7 per end plate (primary sources), which is enough for >10^4 quanta of ACh as estimated by Katz and Miledi (ref 682) and the minuteness of the synaptic gap seem to ensure that most of the ACh molecules would collide with a receptor site within a few ms of their release."
Entered by Uri M
ID 115054