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Published Journal Articles

2018

EFFECTS OF Punica granatum JUICE ON CONTRACTILITY OF ISOLATED AORTA IN FEMALE ALBINO RATS

2018-04
academic journal international university of Erbil (Issue : 25196928) (Volume : 1)
The present study focused on the mechanisms of smooth muscle relaxation induced by Punica granatum juice (PJ) in the rat thoracic aorta. The thoracic aorta was removed from female adult albino rat and placed in an organ bath containing Kreb’s solution and the contractions were recorded isometrically. The results demonstrated that the P. granatum juice (1.5 to 5 mg/ml) significantly reduces the contractions induced by phenylephrine (PE) (0.01 mM), with IC50 ± SEM of 2.859 ± 0.101 mg/ml, and percentage of relaxation for PE-induced contraction was 81.8 ± 0.358. Also, the vasodilatory activity of PJ was not modified by endothelial denuded aorta with IC50 ± SEM 3.389 ± 0.084 mg/ml and the percentage of relaxation was 79.77 ±0.824 %. Pomegranate juice induced relaxation in the PE-induced contraction in intact aorta was unaffected by nitric oxide synthase inhibitor (L-NAME) (3*10-4), gaunyl cyclase inhibitor (methylene blue) (1*10-5) and PGI2 inhibitor (Indomethacin) (3*10-5) with IC50 ± SEM 3.424 ± 0.065, 3.286 ± 0.168 and 3.490 ± 0.054, respectively. The percentage of relaxation was 75.23 ± 0.661, 119.61 ± 4.128 and 83.87 ± 0.715%, respectively. In addition, Pre-incubation of aortic rings with TEA (1mM), GLIB (10-5), BaCl2 (1mM) and 4-AP (1mM) with IC50 ± SEM 3.099 ± 0.049mg/ml, 2.759 ± 0.087mg/ml, 2.889 ± 0.054mg/ml and 2.436±0.049 mg/ml, and the percentages of relaxation were 101.38 ± 0.151%, 88.55±0.58%, 90.25±0.168%, and 104.72±0.939%, respectively. Finally, PJ significantly increased dose-response relaxation after incubation of thoracic aortic rings with Nifedipine (10-6 M) with IC50 ± SEM, 3.495 ± 0.1012 and the percentage of relaxation was 100.276 ± 3.378%.
2017

THE ROLE OF K+ AND CA2+ ION CHANNELS IN Α-TERPINYLE ACETATE-INDUCED VASODILATION IN RAT’S AORTIC RINGS

2017-06
Science Journal of University of Zakho (Issue : 24146943) (Volume : 5)
The monoterpene, α-terpinyle acetate (TA) is a constituent of essential oils present in aromatic plants. Since the role of ion channels and endothelial hyperpolarizing factors in TA induced relaxation in rat’s aorta is unknown, the current study aimed to study the mechanism underlying the vasodilatory effect of TA in isolated aortic rings. Terpinyle acetate induced a potent vasodilation in rat aortic rings with a percentage of relaxation of 63.79 %. The results of the role of K+ channel subtypes in vasorelaxation revealed that both Kv and KATP played a major role since GLIB produced a maximum percent of inhibition in the relaxation produced by TA to 8.91 %; this was followed by 4-AP in which the percent of inhibition reduced to 14.95. On the other hand, Kir played no role in the TA induced vasorelaxation since BaCl2 did not produce any inhibition in aortic relaxation. Furthermore, also L-type Ca2+ channel played no role in TA induced relaxation since the L-type Ca2+ channel inhibitor Nifedipine did not reduce the percent of relaxation. Endothelium also played a considerable role in the induced vasorelaxation since, in denuded aorta, the percent of relaxation was reduced to 36%. Preincubation of the aortic ring with methylene blue, a soluble cGMP inhibitor also significantly reduced the TA induced relaxation to 16.39%. In contrast, preincubation with cyclooxygenase inhibitor Indomethacin did not produce any inhibitory effect on AT induced vasorelaxation. It can be concluded from these novel results that AT induced vasorelaxation involve the activation of KV, KATP channels and at least partly dependent on endothelium via the activation NO-cGMP signal transduction pathway.

1. Effects of punica granatum seed hydromethanol extract on contractility of isolated aorta in female albino rats

2017-03
Science Journal of University of Zakho (Issue : 24146943) (Volume : 5)
The aim of the present study was to evaluate the physiological effect of the Punica granatum hydromethanol seeds extract on the contractility of isolated rat aortic rings. The isolated rat’s thoracic aorta was placed in an organ bath containing Krebs solution and the contraction was recorded isometrically. The results demonstrated that P. granatum hydro- methanol extract (1.5 to 5 mg/ml) caused a significant relaxant effect on the contractions induced by phenylephrine (0.01 mM) with IC50 ± SEM of 2.682 ± 0.197 mg/ml and the percentage of relaxation for PE-induced contraction was 52.88 ± 0.831. In endothelium intact and denuded aortic rings, the extract induced more or less the same response, except at high concentrations used (4.5 – 5.0 mg/ml) in which the endothelium denuded rings produced a significant reduction in the percent of relaxation from 49.91 to 25.42. Relaxant effect of hydromethanol seed extracts on intact aorta was not affected by nitric oxide synthase sinhsibitor ( L-NAME, 3*10-4), gaunyl cyclase inhibitor ( methylene blue 1*10-5) and PGI2 inhibitor (Indomethacin, 3*10-5), and thus, the percentages of relaxation were 59.85 ± 0.084, 58.59 ± 0.566 and 56.76 ± 0.693 respectively. In addition, incubation of aortic rings with the K+ channels blockers TEA, GLIB,, 4AP and BaCl2, that Kca, KATP and Kv channels played no role on vasorelaxation induced by hydromethanol extract, while Kir enhanced the relaxation induced by the extract to76.40%. Finally, hydro methanol extract significantly enhanced dose-response relaxation after incubation of thoracic aortic rings with Nifedipine (10-6 M) to 91.91 % with IC50 ± SEM 1.774 ± 0.096. It can be concluded from the results of the current work that the fraction of Punica granatum hydromethanol seed extract has vasorelaxant effects on rat aortic which was partially dependent on endothelium, Kir and Ca channels.

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