You need JavaScript to view this

Comparison between narcotic 'receptors' in the guinea-pig ileum and the rat brain

Journal Article:

Abstract

The receptors, i.e., specific binding molecules, for narcotic analgesics in the guinea-pig ileum and rat brain have been compared. The relative affinities of a number of narcotics for the two receptors were very similar and discrimination between stereoisomeric agents was identical. The dissociation constants for dihydromorphine binding were 0.78 nM for the ileum and 1.4 nM for the brain receptor, respectively. There was a good correspondance between receptor affinities on the ileum preparation and the literature data on biologic activity on the isolated ileum. Codeine, diphenoxylate, difenoxine and loperamide, which are used clinically for the treatment of diarrhoea showed no selectivity against the ileum receptor. The two latter drugs had a very high receptor affinity and their lack of narcotic activity after oral administration is probably attributable to lack of penetration of the CNS. Receptor binding in both ileum and brain preparations was inhibited by N-ethylmaleimide, Triton X-100, trypsin and phospholipase C. There were small quantitative differences in sensitivity to these agents but it is difficult to assess whether this is because of real differences between the receptor molecules or attributable to secondary effects. As previously described for the brain receptor, the ileum receptor appeared to be present in a  More>>
Authors:
Terenius, L [1] 
  1. Uppsala Univ. (Sweden)
Publication Date:
Jan 01, 1975
Product Type:
Journal Article
Reference Number:
EDB-76-055564
Resource Relation:
Journal Name: Acta Pharmacol. Toxicol.; (Denmark); Journal Volume: 37
Subject:
59 BASIC BIOLOGICAL SCIENCES; ANALGESICS; UPTAKE; BRAIN; CARBON 14 COMPOUNDS; GUINEA PIGS; METABOLISM; MORPHINE; SMALL INTESTINE; ALKALOIDS; ANIMALS; BODY; CENTRAL NERVOUS SYSTEM; DIGESTIVE SYSTEM; DRUGS; GASTROINTESTINAL TRACT; INTESTINES; LABELLED COMPOUNDS; MAMMALS; NARCOTICS; NERVOUS SYSTEM; ORGANIC COMPOUNDS; ORGANS; RODENTS; VERTEBRATES; 550501* - Metabolism- Tracer Techniques
OSTI ID:
7279458
Country of Origin:
Denmark
Language:
English
Other Identifying Numbers:
Journal ID: CODEN: APTOA
Submitting Site:
INIS
Size:
Pages: 211-221
Announcement Date:

Journal Article:

Citation Formats

Terenius, L. Comparison between narcotic 'receptors' in the guinea-pig ileum and the rat brain. Denmark: N. p., 1975. Web.
Terenius, L. Comparison between narcotic 'receptors' in the guinea-pig ileum and the rat brain. Denmark.
Terenius, L. 1975. "Comparison between narcotic 'receptors' in the guinea-pig ileum and the rat brain." Denmark.
@misc{etde_7279458,
title = {Comparison between narcotic 'receptors' in the guinea-pig ileum and the rat brain}
author = {Terenius, L}
abstractNote = {The receptors, i.e., specific binding molecules, for narcotic analgesics in the guinea-pig ileum and rat brain have been compared. The relative affinities of a number of narcotics for the two receptors were very similar and discrimination between stereoisomeric agents was identical. The dissociation constants for dihydromorphine binding were 0.78 nM for the ileum and 1.4 nM for the brain receptor, respectively. There was a good correspondance between receptor affinities on the ileum preparation and the literature data on biologic activity on the isolated ileum. Codeine, diphenoxylate, difenoxine and loperamide, which are used clinically for the treatment of diarrhoea showed no selectivity against the ileum receptor. The two latter drugs had a very high receptor affinity and their lack of narcotic activity after oral administration is probably attributable to lack of penetration of the CNS. Receptor binding in both ileum and brain preparations was inhibited by N-ethylmaleimide, Triton X-100, trypsin and phospholipase C. There were small quantitative differences in sensitivity to these agents but it is difficult to assess whether this is because of real differences between the receptor molecules or attributable to secondary effects. As previously described for the brain receptor, the ileum receptor appeared to be present in a fraction enriched in plasma membranes.}
journal = {Acta Pharmacol. Toxicol.; (Denmark)}
volume = {37}
journal type = {AC}
place = {Denmark}
year = {1975}
month = {Jan}
}