An amplifying effect of exogenous and neurally stored 5-hydroxytryptamine on the neurogenic contraction in rat tail artery
(1991) In British Journal of Pharmacology 102(2). p.401-407- Abstract
- 1. The interactions between sympathetic neuroeffector transmission and 5-hydroxytryptamine (5-HT) were investigated in segments of rat isolated tail artery. 2. Contractile responses to field stimulation of the artery segments were abolished by tetrodotoxin (3 x 10(-7) M). A subthreshold concentration of acutely applied exogenous 5-HT (10(-8) M) markedly enhanced the contractions induced by sympathetic nerve stimulation, through an action on postjunctional 5-HT2-receptors. 3. The amplifying effect of 5-HT involved an enhanced influx of extracellular calcium into the smooth muscle cells. In contrast, the neurogenic contractions in vessels not exposed to 5-HT were not dependent on extracellular calcium. 4. The adrenergic component of the... (More)
- 1. The interactions between sympathetic neuroeffector transmission and 5-hydroxytryptamine (5-HT) were investigated in segments of rat isolated tail artery. 2. Contractile responses to field stimulation of the artery segments were abolished by tetrodotoxin (3 x 10(-7) M). A subthreshold concentration of acutely applied exogenous 5-HT (10(-8) M) markedly enhanced the contractions induced by sympathetic nerve stimulation, through an action on postjunctional 5-HT2-receptors. 3. The amplifying effect of 5-HT involved an enhanced influx of extracellular calcium into the smooth muscle cells. In contrast, the neurogenic contractions in vessels not exposed to 5-HT were not dependent on extracellular calcium. 4. The adrenergic component of the amplified response involved postjunctional alpha 1- but not alpha 2- adrenoceptor activation. 5. Exposure of the vessels to 5-HT (5 x 10(-7) M) for 30 min resulted in uptake of the amine into the perivascular sympathetic nerves, as demonstrated by immunohistochemistry. After chemical sympathectomy with 6-hydroxydopamine in vitro or in vivo, or surgical sympathectomy, there was little or no uptake. 6. Exposure to 5-HT followed by repeated washing resulted in an enhancement of the neurogenic contraction, which was still fully tetrodotoxin-sensitive. The enhanced response was blocked by ketanserin (10(-8) M) and prevented by the presence of the 5-HT uptake blocker, paroxetine (3 x 10(-8) M), during the period of exposure to 5-HT. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1105965
- author
- Szabo, Csaba ; Hardebo, Jan Erik LU and Owman, Christer LU
- organization
- publishing date
- 1991
- type
- Contribution to journal
- publication status
- published
- subject
- in
- British Journal of Pharmacology
- volume
- 102
- issue
- 2
- pages
- 401 - 407
- publisher
- Wiley
- external identifiers
-
- pmid:1849769
- scopus:0026082880
- ISSN
- 1476-5381
- language
- English
- LU publication?
- yes
- id
- f2e72828-5ff6-43e0-b858-069b28f78ff1 (old id 1105965)
- alternative location
- http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1918028
- date added to LUP
- 2016-04-01 16:45:20
- date last changed
- 2021-01-03 09:05:09
@article{f2e72828-5ff6-43e0-b858-069b28f78ff1,
abstract = {{1. The interactions between sympathetic neuroeffector transmission and 5-hydroxytryptamine (5-HT) were investigated in segments of rat isolated tail artery. 2. Contractile responses to field stimulation of the artery segments were abolished by tetrodotoxin (3 x 10(-7) M). A subthreshold concentration of acutely applied exogenous 5-HT (10(-8) M) markedly enhanced the contractions induced by sympathetic nerve stimulation, through an action on postjunctional 5-HT2-receptors. 3. The amplifying effect of 5-HT involved an enhanced influx of extracellular calcium into the smooth muscle cells. In contrast, the neurogenic contractions in vessels not exposed to 5-HT were not dependent on extracellular calcium. 4. The adrenergic component of the amplified response involved postjunctional alpha 1- but not alpha 2- adrenoceptor activation. 5. Exposure of the vessels to 5-HT (5 x 10(-7) M) for 30 min resulted in uptake of the amine into the perivascular sympathetic nerves, as demonstrated by immunohistochemistry. After chemical sympathectomy with 6-hydroxydopamine in vitro or in vivo, or surgical sympathectomy, there was little or no uptake. 6. Exposure to 5-HT followed by repeated washing resulted in an enhancement of the neurogenic contraction, which was still fully tetrodotoxin-sensitive. The enhanced response was blocked by ketanserin (10(-8) M) and prevented by the presence of the 5-HT uptake blocker, paroxetine (3 x 10(-8) M), during the period of exposure to 5-HT.}},
author = {{Szabo, Csaba and Hardebo, Jan Erik and Owman, Christer}},
issn = {{1476-5381}},
language = {{eng}},
number = {{2}},
pages = {{401--407}},
publisher = {{Wiley}},
series = {{British Journal of Pharmacology}},
title = {{An amplifying effect of exogenous and neurally stored 5-hydroxytryptamine on the neurogenic contraction in rat tail artery}},
url = {{http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1918028}},
volume = {{102}},
year = {{1991}},
}