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LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE
Cholinesterase (ChE) activity is present in crustacean muscle extracts. However, since acetylcholine (ACh) is not a neuromuscular transmitter in these animals, the role and exact localization of ChE was unknown. The histochemical localization of the enzyme was studied in whole muscle and in the sarc...
Autores principales: | , |
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Formato: | Texto |
Lenguaje: | English |
Publicado: |
The Rockefeller University Press
1973
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2109090/ https://www.ncbi.nlm.nih.gov/pubmed/4805007 |
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author | Spielholz, Neil I. Van der Kloot, William G. |
author_facet | Spielholz, Neil I. Van der Kloot, William G. |
author_sort | Spielholz, Neil I. |
collection | PubMed |
description | Cholinesterase (ChE) activity is present in crustacean muscle extracts. However, since acetylcholine (ACh) is not a neuromuscular transmitter in these animals, the role and exact localization of ChE was unknown. The histochemical localization of the enzyme was studied in whole muscle and in the sarcoplasmic reticulum fraction of the extract, 50-µm frozen sections of glutaraldehyde-fixed crayfish tail flexor muscle were incubated with acetylthiocholine (ATC) as substrate, and examined under the electron microscope. After some modifications in published techniques, dense deposits were found associated with the sarcolemma, sarcolemmal invaginations, and transverse tubules. No deposits were found in 10(-4) M eserine, or if butyrylthiocholine (BTC) was substituted for ATC. The vesicles in the sarcoplasmic reticulum fraction which demonstrate the activity must represent minced bits of these membranes. Using a spectrophotometric method, the kinetics of the crustacean muscle enzyme was compared to the acetylcholinesterase (AChE) on mammalian red blood cells and in the lobster ventral nerve cord. Surprisingly, and contrary to previous reports, the crustacean muscle enzyme did not demonstrate substrate inhibition. While a number of similarities to AChE were found, this lack of substrate inhibition makes questionable an unequivocal similarity with classical AChE. |
format | Text |
id | pubmed-2109090 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 1973 |
publisher | The Rockefeller University Press |
record_format | MEDLINE/PubMed |
spelling | pubmed-21090902008-05-01 LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE Spielholz, Neil I. Van der Kloot, William G. J Cell Biol Article Cholinesterase (ChE) activity is present in crustacean muscle extracts. However, since acetylcholine (ACh) is not a neuromuscular transmitter in these animals, the role and exact localization of ChE was unknown. The histochemical localization of the enzyme was studied in whole muscle and in the sarcoplasmic reticulum fraction of the extract, 50-µm frozen sections of glutaraldehyde-fixed crayfish tail flexor muscle were incubated with acetylthiocholine (ATC) as substrate, and examined under the electron microscope. After some modifications in published techniques, dense deposits were found associated with the sarcolemma, sarcolemmal invaginations, and transverse tubules. No deposits were found in 10(-4) M eserine, or if butyrylthiocholine (BTC) was substituted for ATC. The vesicles in the sarcoplasmic reticulum fraction which demonstrate the activity must represent minced bits of these membranes. Using a spectrophotometric method, the kinetics of the crustacean muscle enzyme was compared to the acetylcholinesterase (AChE) on mammalian red blood cells and in the lobster ventral nerve cord. Surprisingly, and contrary to previous reports, the crustacean muscle enzyme did not demonstrate substrate inhibition. While a number of similarities to AChE were found, this lack of substrate inhibition makes questionable an unequivocal similarity with classical AChE. The Rockefeller University Press 1973-11-01 /pmc/articles/PMC2109090/ /pubmed/4805007 Text en Copyright © 1973 by The Rockefeller University Press This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/). |
spellingShingle | Article Spielholz, Neil I. Van der Kloot, William G. LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title | LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title_full | LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title_fullStr | LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title_full_unstemmed | LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title_short | LOCALIZATION AND PROPERTIES OF THE CHOLINESTERASE IN CRUSTACEAN MUSCLE |
title_sort | localization and properties of the cholinesterase in crustacean muscle |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2109090/ https://www.ncbi.nlm.nih.gov/pubmed/4805007 |
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