Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum

Andréjak, M. ; Pommier, Y. ; Mouillé, P. ; Schmitt, H.
Springer
Published 1980
ISSN:
1432-1912
Keywords:
Guinea-pig ileum ; Presynaptic α-adrenoceptors ; Clonidine ; Morphine ; α-Adrenoceptor blocking agents
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
Type of Medium:
Electronic Resource
URL:
_version_ 1798295826853789696
autor Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
autorsonst Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
book_url http://dx.doi.org/10.1007/BF00498434
datenlieferant nat_lic_papers
hauptsatz hsatz_simple
identnr NLM200494333
issn 1432-1912
journal_name Naunyn-Schmiedeberg's archives of pharmacology
materialart 1
notes Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
package_name Springer
publikationsjahr_anzeige 1980
publikationsjahr_facette 1980
publikationsjahr_intervall 8019:1980-1984
publikationsjahr_sort 1980
publisher Springer
reference 314 (1980), S. 83-87
schlagwort Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
search_space articles
shingle_author_1 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
shingle_author_2 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
shingle_author_3 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
shingle_author_4 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
shingle_catch_all_1 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
1432-1912
14321912
Springer
shingle_catch_all_2 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
1432-1912
14321912
Springer
shingle_catch_all_3 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
1432-1912
14321912
Springer
shingle_catch_all_4 Andréjak, M.
Pommier, Y.
Mouillé, P.
Schmitt, H.
Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Guinea-pig ileum
Presynaptic α-adrenoceptors
Clonidine
Morphine
α-Adrenoceptor blocking agents
Summary The purpose of the present study was to further characterize the α-adrenoceptors located on parasympathetic fibres. Segments of guinea-pig ileum were stimulated by transmural electrical pulses, and the ensuing contractions, which are due to the release of acetylcholine from postganglionic parasympathetic fibres, were monitored. Clonidine and tramazoline, which are thought to act preferentially on presynaptic α-adrenoceptors, reduced the contractions, whereas phenylephrine and methoxamine, postsynaptic α-adrenoceptor agonists, were ineffective. Contractions induced by acetylcholine were not changed by clonidine but were abolished by atropine. Yohimbine, piperoxan, phentolamine and thymoxamine reversed or prevented the inhibitory effect of clonidine. Prazosin and AR-C239 did not antagonize this effect. The inhibitory effect of tramazoline was antagonized by piperoxan but not by AR-C239 or by prazosin. Naloxone did not alter the action of clonidine, and piperoxan did not change the inhibitory effect of morphine. In conclusion, these experiments suggest the presence on cholinergic postganglionic fibres of both opiate receptors and α-adrenoceptors. The latter appear to resemble more closely α1-adrenoceptors than α1-adrenoceptors.
1432-1912
14321912
Springer
shingle_title_1 Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
shingle_title_2 Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
shingle_title_3 Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
shingle_title_4 Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
sigel_instance_filter dkfz
geomar
wilbert
ipn
albert
fhp
source_archive Springer Online Journal Archives 1860-2000
timestamp 2024-05-06T09:42:23.223Z
titel Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
titel_suche Effects of some α-adrenoceptor agonists and antagonists on the guinea-pig ileum
topic WW-YZ
uid nat_lic_papers_NLM200494333