Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid
In this study, we report the effects of a non-antioxidant flavonoid flavone on vascular reactivity in Wistar–Kyoto (WKY) rat isolated aortae.Whether flavone directly modulates vascular reactivity in spontaneously hypertensive rat (SHR) and streptozotocin-induced diabetic-WKY rat isolated aortae was al...
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| Format: | Article |
| Language: | English |
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Elsevier
2007
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| Online Access: | http://eprints.um.edu.my/2411/1/Modulation_of_vascular_reactivity_in_normal%2C_hypertensive_and_diabetic_rat_aortae_by_a_non-antioxidant_flavonoid.pdf |
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| author | Ajay, M. Achike, F.I. Mustafa, Mohd Rais |
| author_facet | Ajay, M. Achike, F.I. Mustafa, Mohd Rais |
| author_sort | Ajay, M. |
| collection | UM |
| description | In this study, we report the effects of a non-antioxidant flavonoid flavone on vascular reactivity in Wistar–Kyoto (WKY) rat isolated aortae.Whether flavone directly modulates vascular reactivity in spontaneously hypertensive rat (SHR) and streptozotocin-induced diabetic-WKY rat
isolated aortae was also determined. Thoracic aortic rings were mounted in organ chambers and exposed to various drug treatments in the presence of flavone (10 �M) or its vehicle (DMSO), which served as control. Pretreatment with flavone enhanced relaxant effects to endothelium-dependent
vasodilator acetylcholine (ACh) and attenuated contractile effects to �1-receptor agonist phenylephrine (PE) in WKY aortae compared to those observed in control aortic rings. Flavone had no effect on relaxations to ACh in WKY aortae incubated with either l-NAME or methylene
blue, but enhanced relaxations to ACh in WKY aortae incubated with indomethacin or partially depolarized with KCl. Relaxations to ACh are totally abolished in both control or flavone pretreated endothelium-denuded WKY aortae. Flavone attenuated the inhibition by �-NADH of AChinduced relaxation in WKY aortae, but it had no significant effect on the transient contractions induced by �-NADH nor the pyrogallol-induced abolishment of ACh-induced relaxation in WKY aortae. Flavone enhanced endothelium-independent relaxation to sodium nitroprusside (SNP) in
both endothelium-intact and -denuded WKY aortae. Flavone enhanced relaxation to ACh and SNP as well as attenuated contractile effects to PE in SHR and diabetic aortae, a finding similar to that observed in normal WKY aortae. From these results, we conclude that flavone modulates
vascular reactivity in normal as well as hypertensive and diabetic aortae. These effects of flavone results probably through enhanced bioactivity of nitric oxide released from the endothelium. |
| first_indexed | 2024-03-06T05:07:59Z |
| format | Article |
| id | um.eprints-2411 |
| institution | Universiti Malaya |
| language | English |
| last_indexed | 2024-03-06T05:07:59Z |
| publishDate | 2007 |
| publisher | Elsevier |
| record_format | dspace |
| spelling | um.eprints-24112019-12-18T06:22:58Z http://eprints.um.edu.my/2411/ Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid Ajay, M. Achike, F.I. Mustafa, Mohd Rais RM Therapeutics. Pharmacology In this study, we report the effects of a non-antioxidant flavonoid flavone on vascular reactivity in Wistar–Kyoto (WKY) rat isolated aortae.Whether flavone directly modulates vascular reactivity in spontaneously hypertensive rat (SHR) and streptozotocin-induced diabetic-WKY rat isolated aortae was also determined. Thoracic aortic rings were mounted in organ chambers and exposed to various drug treatments in the presence of flavone (10 �M) or its vehicle (DMSO), which served as control. Pretreatment with flavone enhanced relaxant effects to endothelium-dependent vasodilator acetylcholine (ACh) and attenuated contractile effects to �1-receptor agonist phenylephrine (PE) in WKY aortae compared to those observed in control aortic rings. Flavone had no effect on relaxations to ACh in WKY aortae incubated with either l-NAME or methylene blue, but enhanced relaxations to ACh in WKY aortae incubated with indomethacin or partially depolarized with KCl. Relaxations to ACh are totally abolished in both control or flavone pretreated endothelium-denuded WKY aortae. Flavone attenuated the inhibition by �-NADH of AChinduced relaxation in WKY aortae, but it had no significant effect on the transient contractions induced by �-NADH nor the pyrogallol-induced abolishment of ACh-induced relaxation in WKY aortae. Flavone enhanced endothelium-independent relaxation to sodium nitroprusside (SNP) in both endothelium-intact and -denuded WKY aortae. Flavone enhanced relaxation to ACh and SNP as well as attenuated contractile effects to PE in SHR and diabetic aortae, a finding similar to that observed in normal WKY aortae. From these results, we conclude that flavone modulates vascular reactivity in normal as well as hypertensive and diabetic aortae. These effects of flavone results probably through enhanced bioactivity of nitric oxide released from the endothelium. Elsevier 2007-01-19 Article PeerReviewed application/pdf en http://eprints.um.edu.my/2411/1/Modulation_of_vascular_reactivity_in_normal%2C_hypertensive_and_diabetic_rat_aortae_by_a_non-antioxidant_flavonoid.pdf Ajay, M. and Achike, F.I. and Mustafa, Mohd Rais (2007) Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid. Pharmacological Research, 55 (5). pp. 385-391. ISSN 1043-6618, |
| spellingShingle | RM Therapeutics. Pharmacology Ajay, M. Achike, F.I. Mustafa, Mohd Rais Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title | Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title_full | Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title_fullStr | Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title_full_unstemmed | Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title_short | Modulation of vascular reactivity in normal, hypertensive and diabetic rat aortae by a non-antioxidant flavonoid |
| title_sort | modulation of vascular reactivity in normal hypertensive and diabetic rat aortae by a non antioxidant flavonoid |
| topic | RM Therapeutics. Pharmacology |
| url | http://eprints.um.edu.my/2411/1/Modulation_of_vascular_reactivity_in_normal%2C_hypertensive_and_diabetic_rat_aortae_by_a_non-antioxidant_flavonoid.pdf |
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