Vascular mechanisms underlying the hypotensive effect of Rumex acetosa
Context: Rumex acetosa L. (Polygonaceae) is well known in traditional medicine for its therapeutic efficacy as an antihypertensive. Objective: The study investigates antihypertensive potential of crude methanol extract (Ra.Cr) and fractions of Rumex acetosa in normotensive and hypertensive rat model...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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Taylor & Francis Group
2018-01-01
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| Series: | Pharmaceutical Biology |
| Subjects: | |
| Online Access: | http://dx.doi.org/10.1080/13880209.2018.1446031 |
| _version_ | 1818021433791479808 |
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| author | Hafiz Misbah-Ud-Din Qamar Rahila Qayyum Umme Salma Shamim Khan Taous Khan Abdul Jabbar Shah |
| author_facet | Hafiz Misbah-Ud-Din Qamar Rahila Qayyum Umme Salma Shamim Khan Taous Khan Abdul Jabbar Shah |
| author_sort | Hafiz Misbah-Ud-Din Qamar |
| collection | DOAJ |
| description | Context: Rumex acetosa L. (Polygonaceae) is well known in traditional medicine for its therapeutic efficacy as an antihypertensive. Objective: The study investigates antihypertensive potential of crude methanol extract (Ra.Cr) and fractions of Rumex acetosa in normotensive and hypertensive rat models and probes the underlying vascular mechanisms. Materials and methods: Ra.Cr and its fractions were tested in vivo on normotensive and hypertensive Sprague-Dawley rats under anaesthesia for blood pressure lowering effect. In vitro experiments on rat and Oryctolagus cuniculus rabbit aortae were employed to probe the underlying vasorelaxant mechanism. Results: In normotensive rats under anaesthesia, Ra.Cr caused fall in MAP (40 mmHg) at 50 mg/kg with % fall of 27.88 ± 4.55. Among the fractions tested, aqueous fraction was more potent at the dose of 50 mg/kg with % fall of 45.63 ± 2.84. In hypertensive rats under similar conditions, extract and fractions showed antihypertensive effect at same doses while aqueous fraction being more potent, exhibited 68.53 ± 4.45% fall in MAP (70 mmHg). In isolated rat aortic rings precontracted with phenylephrine (PE), Ra.Cr and fractions induced endothelium-dependent vasorelaxation, which was partially blocked in presence of l-NAME, indomethacin and atropine. In isolated rabbit aortic rings pre-contracted with PE and K+-(80 mM), Ra.Cr induced vasorelaxation and shifted Ca2+ concentration–response curves to the right and suppressed PE peak formation, similar to verapamil, in Ca2+-free medium. Discussion and conclusions: The data indicate that l-NAME and atropine-sensitive endothelial-derived NO and COX enzyme inhibitors and Ca2+ entry blocking-mediated vasodilator effect of the extract explain its antihypertensive potential. |
| first_indexed | 2024-04-14T08:18:46Z |
| format | Article |
| id | doaj.art-e2cb9eb551d146639987f6e4aaa0ca77 |
| institution | Directory Open Access Journal |
| issn | 1388-0209 1744-5116 |
| language | English |
| last_indexed | 2024-04-14T08:18:46Z |
| publishDate | 2018-01-01 |
| publisher | Taylor & Francis Group |
| record_format | Article |
| series | Pharmaceutical Biology |
| spelling | doaj.art-e2cb9eb551d146639987f6e4aaa0ca772022-12-22T02:04:19ZengTaylor & Francis GroupPharmaceutical Biology1388-02091744-51162018-01-0156122523410.1080/13880209.2018.14460311446031Vascular mechanisms underlying the hypotensive effect of Rumex acetosaHafiz Misbah-Ud-Din Qamar0Rahila Qayyum1Umme Salma2Shamim Khan3Taous Khan4Abdul Jabbar Shah5COMSATS Institute of Information TechnologyCOMSATS Institute of Information TechnologyCOMSATS Institute of Information TechnologyCOMSATS Institute of Information TechnologyCOMSATS Institute of Information TechnologyCOMSATS Institute of Information TechnologyContext: Rumex acetosa L. (Polygonaceae) is well known in traditional medicine for its therapeutic efficacy as an antihypertensive. Objective: The study investigates antihypertensive potential of crude methanol extract (Ra.Cr) and fractions of Rumex acetosa in normotensive and hypertensive rat models and probes the underlying vascular mechanisms. Materials and methods: Ra.Cr and its fractions were tested in vivo on normotensive and hypertensive Sprague-Dawley rats under anaesthesia for blood pressure lowering effect. In vitro experiments on rat and Oryctolagus cuniculus rabbit aortae were employed to probe the underlying vasorelaxant mechanism. Results: In normotensive rats under anaesthesia, Ra.Cr caused fall in MAP (40 mmHg) at 50 mg/kg with % fall of 27.88 ± 4.55. Among the fractions tested, aqueous fraction was more potent at the dose of 50 mg/kg with % fall of 45.63 ± 2.84. In hypertensive rats under similar conditions, extract and fractions showed antihypertensive effect at same doses while aqueous fraction being more potent, exhibited 68.53 ± 4.45% fall in MAP (70 mmHg). In isolated rat aortic rings precontracted with phenylephrine (PE), Ra.Cr and fractions induced endothelium-dependent vasorelaxation, which was partially blocked in presence of l-NAME, indomethacin and atropine. In isolated rabbit aortic rings pre-contracted with PE and K+-(80 mM), Ra.Cr induced vasorelaxation and shifted Ca2+ concentration–response curves to the right and suppressed PE peak formation, similar to verapamil, in Ca2+-free medium. Discussion and conclusions: The data indicate that l-NAME and atropine-sensitive endothelial-derived NO and COX enzyme inhibitors and Ca2+ entry blocking-mediated vasodilator effect of the extract explain its antihypertensive potential.http://dx.doi.org/10.1080/13880209.2018.1446031calcium channel blockerno-mediated vasorelaxantantihypertensive |
| spellingShingle | Hafiz Misbah-Ud-Din Qamar Rahila Qayyum Umme Salma Shamim Khan Taous Khan Abdul Jabbar Shah Vascular mechanisms underlying the hypotensive effect of Rumex acetosa Pharmaceutical Biology calcium channel blocker no-mediated vasorelaxant antihypertensive |
| title | Vascular mechanisms underlying the hypotensive effect of Rumex acetosa |
| title_full | Vascular mechanisms underlying the hypotensive effect of Rumex acetosa |
| title_fullStr | Vascular mechanisms underlying the hypotensive effect of Rumex acetosa |
| title_full_unstemmed | Vascular mechanisms underlying the hypotensive effect of Rumex acetosa |
| title_short | Vascular mechanisms underlying the hypotensive effect of Rumex acetosa |
| title_sort | vascular mechanisms underlying the hypotensive effect of rumex acetosa |
| topic | calcium channel blocker no-mediated vasorelaxant antihypertensive |
| url | http://dx.doi.org/10.1080/13880209.2018.1446031 |
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