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- Publisher Website: 10.1113/jphysiol.1975.sp010900
- Scopus: eid_2-s2.0-0016715040
- PMID: 167162
- WOS: WOS:A1975W282600011
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Article: Inhibition of adrenergic neurotransmission in isolated veins of the dog by potassium ions
Title | Inhibition of adrenergic neurotransmission in isolated veins of the dog by potassium ions |
---|---|
Authors | |
Issue Date | 1975 |
Publisher | Wiley-Blackwell Publishing Ltd.. The Journal's web site is located at http://www.wiley.com/bw/journal.asp?ref=0022-3751 |
Citation | Journal Of Physiology, 1975, v. 246 n. 2, p. 479-500 How to Cite? |
Abstract | In the intact organism, an increase in K+ concentration decreases the reactivity of blood vessels to sympathetic stimulation. The present experiments were designed to determine whether or not K+ interferes with adrenergic neurotransmission. Helical strips cut from dogs' saphenous veins were incubated in Krebs Ringer solution containing [7 3H]norepinephrine (5 x 10-8 g/ml). The preparations were mounted for superfusion and isometric tension recording; the superfusate was collected for estimation of total radioactivity and for chromatographic separation of 3H labelled norepinephrine and metabolites. Supramaximal electric stimulation (5 Hz, 9 V, 2 msec) increased the tension and the [3H]norepinephrine efflux. Increasing the K+ concentration from 5.9 to 10, 15, and 20 m equiv/l. caused a progressive depression of these contractions and diminished the total 3H efflux in proportion to the relaxation; the decrease in 3H efflux reflected a decrease in intact [3H]norepinephrine. The same increase in K+ concentration did not alter basal tension or basal 3H efflux. Addition of tyramine (4 x 10-6 g/ml. min) to the superfusate augmented both the tension and the efflux, but these actions were not depressed by increasing the K+ concentration. Cocaine, phentolamine, and phenoxybenzamine did not prevent the depression by K+ of the response to electric stimulation. These experiments show that K+ causes relaxation of venous smooth muscle constricted by sympathetic stimulation and does so by inhibiting the release of norepinephrine from nerve endings. By contrast, K+ does not inhibit norepinephrine release in response to tyramine. During submaximal electric stimulation (5 Hz, 1.8-3 V, 2 msec), increasing the K+ concentration from 5.9 to 10 and 15 m equiv/l. potentiated the contractions and increased the [3H]norepinephrine efflux; at 20 m equiv/l., K+ caused transient increases in tension and 3H efflux followed by relaxation and decreased norepinephrine release. After addition of cocaine (10-5 g/ml. min), K+ only caused relaxation and decrease in 3H efflux, showing that, in addition to inhibition of norepinephrine release, K+ also inhibits the reuptake process. In higher concentrations (40 m equiv/l.), K+ caused both a liberation of norepinephrine and a direct activation of the smooth muscle cells. |
Persistent Identifier | http://hdl.handle.net/10722/170507 |
ISSN | 2021 Impact Factor: 6.228 2020 SCImago Journal Rankings: 1.802 |
ISI Accession Number ID |
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Lorenz, RR | en_US |
dc.contributor.author | Vanhoutte, PM | en_US |
dc.date.accessioned | 2012-10-30T06:09:44Z | - |
dc.date.available | 2012-10-30T06:09:44Z | - |
dc.date.issued | 1975 | en_US |
dc.identifier.citation | Journal Of Physiology, 1975, v. 246 n. 2, p. 479-500 | en_US |
dc.identifier.issn | 0022-3751 | en_US |
dc.identifier.uri | http://hdl.handle.net/10722/170507 | - |
dc.description.abstract | In the intact organism, an increase in K+ concentration decreases the reactivity of blood vessels to sympathetic stimulation. The present experiments were designed to determine whether or not K+ interferes with adrenergic neurotransmission. Helical strips cut from dogs' saphenous veins were incubated in Krebs Ringer solution containing [7 3H]norepinephrine (5 x 10-8 g/ml). The preparations were mounted for superfusion and isometric tension recording; the superfusate was collected for estimation of total radioactivity and for chromatographic separation of 3H labelled norepinephrine and metabolites. Supramaximal electric stimulation (5 Hz, 9 V, 2 msec) increased the tension and the [3H]norepinephrine efflux. Increasing the K+ concentration from 5.9 to 10, 15, and 20 m equiv/l. caused a progressive depression of these contractions and diminished the total 3H efflux in proportion to the relaxation; the decrease in 3H efflux reflected a decrease in intact [3H]norepinephrine. The same increase in K+ concentration did not alter basal tension or basal 3H efflux. Addition of tyramine (4 x 10-6 g/ml. min) to the superfusate augmented both the tension and the efflux, but these actions were not depressed by increasing the K+ concentration. Cocaine, phentolamine, and phenoxybenzamine did not prevent the depression by K+ of the response to electric stimulation. These experiments show that K+ causes relaxation of venous smooth muscle constricted by sympathetic stimulation and does so by inhibiting the release of norepinephrine from nerve endings. By contrast, K+ does not inhibit norepinephrine release in response to tyramine. During submaximal electric stimulation (5 Hz, 1.8-3 V, 2 msec), increasing the K+ concentration from 5.9 to 10 and 15 m equiv/l. potentiated the contractions and increased the [3H]norepinephrine efflux; at 20 m equiv/l., K+ caused transient increases in tension and 3H efflux followed by relaxation and decreased norepinephrine release. After addition of cocaine (10-5 g/ml. min), K+ only caused relaxation and decrease in 3H efflux, showing that, in addition to inhibition of norepinephrine release, K+ also inhibits the reuptake process. In higher concentrations (40 m equiv/l.), K+ caused both a liberation of norepinephrine and a direct activation of the smooth muscle cells. | en_US |
dc.language | eng | en_US |
dc.publisher | Wiley-Blackwell Publishing Ltd.. The Journal's web site is located at http://www.wiley.com/bw/journal.asp?ref=0022-3751 | en_US |
dc.relation.ispartof | Journal of Physiology | en_US |
dc.subject.mesh | Animals | en_US |
dc.subject.mesh | Biological Transport, Active - Drug Effects | en_US |
dc.subject.mesh | Cocaine - Pharmacology | en_US |
dc.subject.mesh | Dogs | en_US |
dc.subject.mesh | Electric Stimulation | en_US |
dc.subject.mesh | Muscle, Smooth - Drug Effects | en_US |
dc.subject.mesh | Norepinephrine - Metabolism | en_US |
dc.subject.mesh | Phenoxybenzamine - Pharmacology | en_US |
dc.subject.mesh | Phentolamine - Pharmacology | en_US |
dc.subject.mesh | Potassium - Pharmacology | en_US |
dc.subject.mesh | Saphenous Vein - Drug Effects - Innervation - Metabolism | en_US |
dc.subject.mesh | Sympathetic Nervous System - Physiology | en_US |
dc.subject.mesh | Synaptic Transmission - Drug Effects | en_US |
dc.subject.mesh | Tyramine - Pharmacology | en_US |
dc.title | Inhibition of adrenergic neurotransmission in isolated veins of the dog by potassium ions | en_US |
dc.type | Article | en_US |
dc.identifier.email | Vanhoutte, PM:vanhoutt@hku.hk | en_US |
dc.identifier.authority | Vanhoutte, PM=rp00238 | en_US |
dc.description.nature | link_to_subscribed_fulltext | en_US |
dc.identifier.doi | 10.1113/jphysiol.1975.sp010900 | - |
dc.identifier.pmid | 167162 | - |
dc.identifier.scopus | eid_2-s2.0-0016715040 | en_US |
dc.identifier.volume | 246 | en_US |
dc.identifier.issue | 2 | en_US |
dc.identifier.spage | 479 | en_US |
dc.identifier.epage | 500 | en_US |
dc.identifier.isi | WOS:A1975W282600011 | - |
dc.publisher.place | United Kingdom | en_US |
dc.identifier.scopusauthorid | Lorenz, RR=7402095192 | en_US |
dc.identifier.scopusauthorid | Vanhoutte, PM=7202304247 | en_US |
dc.identifier.issnl | 0022-3751 | - |