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Toprak K, Inanır M, Memioğlu T, Palice A, Kaplangoray M, Yesilay AB, Tascanov MB, Altıparmak İH, Demirbağ R. Effect of Hand Dominance on Radial Artery Spasm and Occlusion: A Prospective Observational Study. Angiology 2024; 75:340-348. [PMID: 36745059 DOI: 10.1177/00033197231155599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transradial access has become the most commonly used method for cardiac catheterization. Many medical and technical applications have been proposed to reduce TRA complications. The aim of this study is to examine the effect of hand dominance on radial artery spasm and radial artery occlusionin subjects undergoing CC via TRA. Between April 2020 and August 2022, 1713 subjects who underwent CC via TRA were included in the study. Patient data were obtained in terms of hand dominance of the catheterized side and RAS and RAO during a 1-month follow-up period. RAS was seen in 9.6% of the subjects. The RAS in patients catheterized by the dominant hand was significantly higher than that performed by the non-dominant hand (12 vs 7.8%; P = .004). RAO was seen in 1% of the subjects. RAO was significantly higher in the spasm side than in the no-spasm side (3 vs .8%; P = .009). Hand dominance was determined as an independent predictor of radial artery spasm (P = .006). In our study, RAS and RAO were more common on the dominant hand side than on the non-dominant side. Choosing the non-dominant hand for TRA for CC may reduce the incidence of RAS and RAO.
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Affiliation(s)
- Kenan Toprak
- Department of Cardiology, Harran University Faculty of Medicine, Sanliurfa, Turkey
| | - Mehmet Inanır
- Cardiology Department, Bolu Abant Izzet Baysal University Faculty of Medicine, Bolu, Turkey
| | - Tolga Memioğlu
- Cardiology Department, Bolu Abant Izzet Baysal University Faculty of Medicine, Bolu, Turkey
| | - Ali Palice
- Sanliurfa Mehmet Akif İnan Training and Research Hospital, Sanlıurfa, Turkey
| | - Mustafa Kaplangoray
- Sanliurfa Mehmet Akif İnan Training and Research Hospital, Sanlıurfa, Turkey
| | - Asuman Biçer Yesilay
- Department of Cardiology, Harran University Faculty of Medicine, Sanliurfa, Turkey
| | | | | | - Recep Demirbağ
- Department of Cardiology, Harran University Faculty of Medicine, Sanliurfa, Turkey
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He GW, Taggart DP. Spasm in Arterial Grafts in Coronary Artery Bypass Grafting Surgery. Ann Thorac Surg 2016; 101:1222-9. [DOI: 10.1016/j.athoracsur.2015.09.071] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 08/21/2015] [Accepted: 09/21/2015] [Indexed: 11/28/2022]
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Lee MY, Lai WT. Low plasma renin level is associated with the occurrence of angiographic radial artery spasm in patients undergoing transradial coronary procedures. Int J Cardiol 2014; 176:1195-7. [DOI: 10.1016/j.ijcard.2014.07.232] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 07/27/2014] [Indexed: 11/17/2022]
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Pagán RM, Martínez AC, Hernández M, Martínez MP, García-Sacristán A, Correa C, Novella S, Hermenegildo C, Prieto D, Benedito S. Endothelial and neural factors functionally involved in the modulation of noradrenergic vasoconstriction in healthy pig internal mammary artery. Biochem Pharmacol 2012; 83:882-92. [PMID: 22260985 DOI: 10.1016/j.bcp.2011.12.038] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 12/21/2011] [Accepted: 12/27/2011] [Indexed: 10/14/2022]
Abstract
The role of endothelial and neural factors as modulators of neurogenic- and noradrenaline-induced vasoconstriction was examined in healthy pig internal mammary artery (IMA). Tetrodotoxin-, guanethidine-sensitive electrical field stimulation (EFS)-, and noradrenaline-elicited contractions were significantly diminished by prazosin (n=8, P<0.001) and less so by rauwolscine, indicating functional α₁- and α₂-adrenoceptor-mediated noradrenergic innervation of the IMA. Endothelium removal reduced neurogenic (n=8, P<0.01) but augmented noradrenaline responses (n=8, P<0.01), suggesting the release of two endothelium-dependent factors with opposite effects. In the presence of endothelium, neurogenic and exogenous noradrenaline vasoconstrictions were enhanced by L-NOArg (n=7, P<0.05 and P<0.01 respectively) and ODQ (n=7, both P<0.05); in denuded arteries, nNOS inhibition with N(ω)-propyl-L-arginine increased neurogenic contraction (n=7, P<0.05). Western blotting indicated the presence of neural and endothelial origin NO (n=6, P<0.001). Tetraethylammonium (n=9, P<0.001), iberiotoxin (n=7, P<0.001) and 4-aminopyridine (n=8, P<0.01) enhanced vasoconstrictions revealing a modulatory role of big conductance Ca²⁺-activated K⁺ (BK(Ca)) and voltage-dependent K⁺ (K(v)) channels in noradrenergic responses. Bosentan pretreatment (n=8, P<0.05) suggested endothelin-1 as the inferred contractile neurogenic endothelial-dependent factor. Indomethacin-induced inhibition involved a muscular prostanoid (n=9, P<0.05), functionally and immunologically localized, and derived from cyclooxygenase (COX)-1 and COX-2, as revealed by Western blots (n=5, P=0.1267). Thus, noradrenergic IMA contractions are controlled by contractile prostanoid activation and endothelin-1 release, and offset by BK(Ca) and K(v) channels and neural and endothelial NO. These results help clarify the mechanisms of vasospasm in IMA, as the preferred vessel for coronary bypass.
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Affiliation(s)
- Rosa María Pagán
- Departamento de Fisiología, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
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Effect of potassium channel opener pinacidil on the contractions elicited electrically or by noradrenaline in the human radial artery. Eur J Pharmacol 2011; 654:266-73. [DOI: 10.1016/j.ejphar.2010.12.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 11/25/2010] [Accepted: 12/19/2010] [Indexed: 11/23/2022]
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Effects of Axial Stretch on Cell Proliferation and Intimal Thickness in Arteries in Organ Culture. Cell Mol Bioeng 2010; 3:286-295. [PMID: 21116478 DOI: 10.1007/s12195-010-0128-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Intimal hyperplasia (IH) remains the major cause of intermediate and long-term failure of vascular grafts and endovascular interventions. Arteries are subjected to a significant longitudinal stress in addition to the shear stress and tensile stress from the blood flow. The aim of this study was to determine the effect of axial stretch on cell proliferation and IH in arteries. Porcine carotid arteries, intact or endothelial cell (EC) denudated, were maintained ex vivo at different stretch ratios (1.3, 1.5, and 1.8) and flow rates (16 or 160 mL/min) while remaining at physiologic pressure for 7 days. The viability of the arteries was verified with norepinephrine, carbachol, and sodium nitroprusside stimulations, and the cell proliferation was detected using bromodeoxyuridine labeling and immunostaining. Our results showed that the axial stretch ratio did not significantly affect intimal thickness and cell proliferation in normal arteries. However, axial stretch increased the neointimal thickness in EC denudated arteries cultured under low flow conditions. The cell proliferation increased significantly in the intima and inner half of the media of the EC denudated arteries under normal or elevated axial stretch in comparison to intact arteries at the same stretch ratio. These results demonstrated that axial stretch with EC denudation and low flow increases neointimal formation and cell proliferation in the arteries.
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Martínez AC, Pagán RM, Prieto D, Recio P, García-Sacristán A, Hernández M, Benedito S. Modulation of noradrenergic neurotransmission in isolated rat radial artery. J Pharmacol Sci 2010; 111:299-311. [PMID: 19926936 DOI: 10.1254/jphs.09135fp] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
The present study was designed to characterize the neurogenic contraction of rat radial artery. Electrical field stimulation (EFS) evoked frequency-dependent contraction that was abolished by tetrodotoxin (neuronal Na(+) channel blocker), guanethidine (sympathetic neuron blocker), or phentolamine (alpha-adrenoceptor blocker). The alpha(1)-adrenoceptor antagonist prazosin inhibited endothelium-independent contractions to EFS, noradrenaline (NA), and the alpha(1)-adrenoceptor agonist phenylephrine. Rauwolscine, an alpha(2)-adrenoceptor antagonist, augmented nerve-mediated contractions and reduced sensitivity to NA and the alpha(2)-adrenoceptor agonist BHT-920. The beta-adrenoceptor antagonist propranolol diminished EFS-elicited contractions, while sensitivity to NA was enhanced by propranolol. Relaxations evoked by isoproterenol, a beta-adrenoceptor agonist, were abolished by propranolol. N(G)-Nitro-L-arginine (L-NOARG), a nitric oxide (NO) synthase inhibitor, increased both nerve-mediated and NA-induced responses in endothelium-intact, but not in endothelium-denuded arteries. Moreover, endothelium-dependent responses to BHT-920 and isoproterenol were modified by L-NOARG. Tetraethylammonium (TEA) or 4-aminopyridine, the Ca2+-activated (K(Ca)) or voltage-dependent K+ (K(V)) channel blockers, respectively, enhanced the neurogenic contractions observed. TEA but not 4-aminopyridine increased NA-induced contractions. The ATP-sensitive K+ (K(ATP))-channel blocker glibenclamide failed to modify adrenergic contractions. Blockade of capsaicin-sensitive primary afferents increased EFS-induced contractions. In conclusion, adrenergic contractions are predominantly mediated by muscular alpha(1)-adrenoceptors, while endothelial alpha(2)- and beta-adrenoceptors play a minor role. Presynaptic alpha(2)- and beta-adrenoceptors cannot be precluded. Noradrenergic neurotransmission in rat radial artery seems to be modulated by both stimulation of endothelial NO, K(Ca), and K(V) channels and sensory C-fiber activation.
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Characteristics of the antivasoconstrictor effect of pinacidil on isolated radial artery. ACTA VET-BEOGRAD 2010. [DOI: 10.2298/avb1003145g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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TANAKA N. Pharmacological Studies on Responsiveness of 5-Hydroxytryptamine to Overcome Perioperative Spasm of Coronary Artery Bypass Graft. YAKUGAKU ZASSHI 2009; 129:1049-53. [DOI: 10.1248/yakushi.129.1049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Naoko TANAKA
- First Department of Pharmacology, School of Pharmaceutical Sciences, Kyushu University of Health and Welfare
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Pagán RM, Martínez AC, Martínez MP, Hernández M, García-Sacristán A, Correa C, Prieto D, Benedito S. Endothelial and potassium channel dependent modulation of noradrenergic vasoconstriction in the pig radial artery. Eur J Pharmacol 2009; 616:166-74. [PMID: 19527707 DOI: 10.1016/j.ejphar.2009.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 05/18/2009] [Accepted: 06/03/2009] [Indexed: 11/28/2022]
Abstract
The localisation and function of noradrenergic perivascular innervation of the radial artery were examined in a porcine model. Through immunohistochemical techniques, we explored the possible existence of dopamine beta-hydroxylase and choline-acetyltransferase in the nerve fibres supplying the radial artery. Arterial rings suspended in organ baths were used to isometrically record tension in functional tests designed to determine the vasoconstriction response to electrical field stimulation (EFS) or exogenous noradrenaline. Morphological studies revealed the presence of noradrenergic, but not cholinergic, nerve fibres in the tunica adventitia and adventitia-media boundary of the artery wall. EFS-elicited frequency-dependent contractions (EF(50)=3.37+/-0.19 Hz and E(max)=87.7+/-3.8%; n=47) were abolished by tetrodotoxin. The contractile effect was markedly reduced by guanethidine, phentolamine and prazosin and slightly inhibited by rauwolscine, but unaltered by propranolol, atropine, bosentan or capsaicine. Endothelium removal increased EFS-evoked contractions but the addition of L-NOArg, ODQ or indomethacin had no effect. Pre-incubation with tetraethylammonium and 4-aminopyridine, but not glibenclamide, enhanced these neurogenic responses. SOD and apocynin reduced EFS-elicited responses at low frequencies. Exposure of the arterial rings to the same agents did not affect the noradrenaline concentration-response curves except for the alpha-adrenoceptor antagonists. These results led to the conclusions that neurogenic contractions in the pig radial artery are predominantly mediated by noradrenaline released from periarterial adrenergic nerves. This neurogenic vasoconstriction is modulated by a non-NO, non-prostanoid endothelium-dependent relaxing factor and by Ca(2+)-activated and voltage-dependent K(+) channels.
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Affiliation(s)
- Rosa María Pagán
- Department of Physiology, Faculty of Pharmacy, Universidad Complutense de Madrid, Madrid, Spain
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Yoshizaki T, Tabuchi N, Toyama M. Verapamil and Nitroglycerin Improves the Patency Rate of Radial Artery Grafts. Asian Cardiovasc Thorac Ann 2008; 16:396-400. [DOI: 10.1177/021849230801600511] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The best way to prevent spasm of the radial artery is still under investigation. We retrospectively compared the effectiveness of topical verapamil-nitroglycerin with papaverine in preventing graft spasm in 215 patients who underwent isolated conventional coronary artery bypass using a radial artery. Postoperative angiographic data were successfully collected in 116 patients. Perioperative radial artery graft spasm was observed in 2 patients in the papaverine group and 1 in the verapamil-nitroglycerin group; this difference was not considered significant. Complete or functional occlusion was detected by postoperative angiography in 13 grafts (10 in the papaverine group and 3 in the verapamil-nitroglycerin group). Multivariate regression analysis revealed that topical papaverine and grafting to the right coronary artery significantly increased the rate of occlusion of radial artery grafts. Although further studies are needed, our data support the view that topical verapamil-nitroglycerin reduces the incidence of radial artery graft occlusion.
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Affiliation(s)
| | | | - Masaaki Toyama
- Department of Cardiovascular Surgery, Kameda Medical Center, Chiba, Japan
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Tanaka N, Nakamura E, Ohkura M, Kuwabara M, Yamashita A, Onitsuka T, Asada Y, Hisa H, Yamamoto R. BOTH 5-HYDROXYTRYPTAMINE 5-HT2AAND 5-HT1BRECEPTORS ARE INVOLVED IN THE VASOCONSTRICTOR RESPONSE TO 5-HT IN THE HUMAN ISOLATED INTERNAL THORACIC ARTERY. Clin Exp Pharmacol Physiol 2008; 35:836-40. [DOI: 10.1111/j.1440-1681.2008.04933.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Attaran S, John L, El-Gamel A. Clinical and Potential Use of Pharmacological Agents to Reduce Radial Artery Spasm in Coronary Artery Surgery. Ann Thorac Surg 2008; 85:1483-9. [PMID: 18355566 DOI: 10.1016/j.athoracsur.2007.10.042] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2007] [Revised: 10/09/2007] [Accepted: 10/10/2007] [Indexed: 11/17/2022]
Affiliation(s)
- Saina Attaran
- Department of Cardiothoracic Surgery, Kings College Hospital, London, United Kingdom
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Choudhary BP, Antoniades C, Brading AF, Galione A, Channon K, Taggart DP. Diabetes mellitus as a predictor for radial artery vasoreactivity in patients undergoing coronary artery bypass grafting. J Am Coll Cardiol 2007; 50:1047-53. [PMID: 17825713 DOI: 10.1016/j.jacc.2007.06.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 05/02/2007] [Accepted: 06/03/2007] [Indexed: 01/08/2023]
Abstract
OBJECTIVES Our purpose was to examine the impact of diabetes mellitus (DM) on vasoreactivity and endothelial function of radial artery (RA) grafts ex vivo. BACKGROUND The arteriopathy associated with DM may influence the surgeon's choice of conduits for revascularization. Arterial conduits and especially the RA are prone to vasospasm in the perioperative period. METHODS The study population consisted of 98 patients with coronary artery disease undergoing coronary artery bypass grafting by using RA grafts. The maximum contractions of RA segments induced by K+ (66 mmol/l) and clinically important vasoconstrictors such as adrenaline (5 x 10(-5) mol/l), angiotensin II (10(-6) mol/l), and prostaglandin F2alpha (PGF2alpha) (10(-6) mol/l) were recorded. Relaxation of RA rings to carbachol (10(-4) mol/l) was used as a measure of endothelial function. Multivariate analysis was then applied to determine the role of clinical characteristics on the vasomotor responses to these agents. RESULTS Vessels from patients with DM had greater contractions in response to adrenaline (p < 0.05), angiotensin (p < 0.05), and PGF2alpha (p < 0.01) compared with non-DM vessels, despite the similar vasoconstrictions induced by high K+ (p = NS). Diabetes mellitus was also associated with smaller vasorelaxations in response to carbachol (p < 0.001). In multivariate analysis, DM was an independent predictor of RA contractions in response to adrenaline (beta [SE] 3.085 [1.410], p = 0.031), angiotensin II (beta [SE] 3.838 [1.552], p = 0.015), and PGF2alpha (beta [SE] 4.609 [1.908], p = 0.018) but not K+ (p = NS). Diabetes mellitus was also independently associated with the vasorelaxations in response to carbachol (beta [SE] -15.645 [2.622], p = 0.0001). CONCLUSIONS Diabetes mellitus is associated with impaired endothelial function and greater contractions of RA grafts in response to all of the clinically relevant vasoconstrictors. These findings suggest that the RA of diabetic patients may be more prone to spasm in response to endogenous vasoconstrictors, an observation with important implications for surgeons' choice of conduits in this cohort of patients.
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Affiliation(s)
- Bikram P Choudhary
- Department of Cardiothoracic Surgery, John Radcliffe Hospital, Oxford, United Kingdom
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Ozdemir C, Ikizler M, Besogul Y, Karakaya A, Sirmagul B. An alternative agent for radial arterial graft spasm: application of topical iloprost. SCAND CARDIOVASC J 2007; 41:201-6. [PMID: 17487772 DOI: 10.1080/14017430601150601] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
OBJECTIVE This study is planned bringing about a new choice for the prophylaxis of RA spasm which is topical iloprost and compares its efficacy with papaverine and diltiazem. DESIGN Twenty eight CABG patients with RA grafts were categorized into four groups by taking into account the topical vasodilator (papaverine, diltiazem, iloprost and saline) that was utilized during harvesting. Arterial segments were separated into four rings and were than soaked with KCL, norepinephrine, phenylephrine and serotonin. Then, acetylcholine was given to induce relaxation and the preparations were put to rest for 10 minute. RESULTS The contraction response achieved by the vasoreactive agents was most effectively inhibited by papaverine. The effectiveness of the response obtained by iloprost was similar to that of papaverine and significantly stronger than that of diltiazem. Especially at high vasoreactive substance concentrations, diltiazem had a contraction close to that of the control while the protective effect was weaker than those of papaverine and iloprost. CONCLUSION Iloprost can be recommended as a strong alternative to the topical agents used for preventing arterial graft spasm.
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Affiliation(s)
- Coskun Ozdemir
- Department of Cardiovascular Surgery, Medical School of Eskisehir Osmangazi University, Turkey
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Stojnic N, Gojkovic-Bukarica L, Peric M, Grbovic L, Lesic A, Bumbasirevic M, Heinle H. Potassium channel opener pinacidil induces relaxation of the isolated human radial artery. J Pharmacol Sci 2007; 104:122-9. [PMID: 17538231 DOI: 10.1254/jphs.fp0061434] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Taking into consideration that the search for drugs capable of modifying blood flow through human radial artery (RA) is warranted, the present study was designed to examine the vasodilatatory effects of the potassium channel opener, pinacidil on the RA and to define the contribution of different K+ -channel subtypes in the endothelium-independent pinacidil action on this blood vessel. Pinacidil relaxed the RA rings with endothelium and without endothelium with comparable potency. N-nitro-L-arginine methyl ester (L-NAME) and methylene blue did not affect the pinacidil-induced vasorelaxation in rings with endothelium. In the rings without endothelium, the K+ -channel blockers glibenclamide and tetraethylammonium (TEA) moderately antagonized the pinacidil-induced relaxation, while charybdotoxin and 4-aminopiridine did not. In endothelium-denuded rings, precontracted with 100 mM K+, the relaxant responses to pinacidil were highly significantly shifted to the right compared to those obtained in RA precontracted with phenylephrine, but pinacidil-induced maximal relaxation was not affected. Addition of nifedipine did not but addition of nifedipine and nickel (Na+ -Ca2+ exchanger inhibitor) did cause a statistically significant rightward shift of the pinacidil concentration-relaxation curve, although the effect 0.1 mM pinacidil was preserved. Thus, pinacidil induces relaxation of the human RA in endothelium-independent manner, and glibenclamide- and TEA-sensitive vascular smooth muscle K+ channels are probably involved. Its ability to completely relax the RA precontracted with K+ -rich solution suggests that pinacidil has additional K+ channel-independent mechanism(s) of action. It seems that stimulation of the forward mode of the Na+ -Ca2+ exchanger plays a part in this K+ channel-independent effect of pinacidil.
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Affiliation(s)
- Natasa Stojnic
- Department of Clinical Pharmacology, Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, Belgrade 11129, Serbia
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Seyrek M, Yildiz O, Ulusoy HB, Yildirim V. Testosterone Relaxes Isolated Human Radial Artery by Potassium Channel Opening Action. J Pharmacol Sci 2007; 103:309-16. [PMID: 17380036 DOI: 10.1254/jphs.fp0060883] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Preliminary clinical studies of testosterone therapy in male patients with coronary artery disease obtained promising results. However, little is known about the in vitro effects of testosterone in human isolated arteries. We investigated the effect of testosterone on contractile tone of human isolated radial artery (RA). Testosterone was added (0.1 - 300 microM ) cumulatively to organ baths after precontraction with KCl (45 mM) and phenylephrine (PE, 10 microM). Testosterone-induced relaxations were tested in the presence of the cyclooxygenase inhibitor indomethacin (10 microM), nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME, 100 microM), non-selective large conductance Ca(2+)-activated and voltage-sensitive K(+) channel inhibitor tetraethylammonium (TEA, 1 mM), ATP-sensitive K(+) channel inhibitor glibenclamide (GLI, 10 microM), and voltage-sensitive K(+) channel inhibitor 4-aminopyridine (4-AP, 1 mM). Testosterone produced relaxation in human RA (E(max): 53.03 +/- 2.76% and 66.83 +/- 1.97% of KCl and PE-induced contraction, respectively). Except for GLI, the relaxation to testosterone is affected by neither K(+) channel inhibitors (TEA, BaCl(2), and 4-AP), L-NAME, nor indomethacin. We report for the first time that supraphysiological concentrations of testosterone induces relaxation in RA. This response may occur in part via ATP-sensitive K(+) channel opening action.
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Affiliation(s)
- Melik Seyrek
- Department of Pharmacology, Gulhane School of Medicine, Ankara, Turkey
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