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Juin SK, Ouseph R, Gondim DD, Jala VR, Sen U. Diabetic Nephropathy and Gaseous Modulators. Antioxidants (Basel) 2023; 12:antiox12051088. [PMID: 37237955 DOI: 10.3390/antiox12051088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/05/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
Diabetic nephropathy (DN) remains the leading cause of vascular morbidity and mortality in diabetes patients. Despite the progress in understanding the diabetic disease process and advanced management of nephropathy, a number of patients still progress to end-stage renal disease (ESRD). The underlying mechanism still needs to be clarified. Gaseous signaling molecules, so-called gasotransmitters, such as nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S), have been shown to play an essential role in the development, progression, and ramification of DN depending on their availability and physiological actions. Although the studies on gasotransmitter regulations of DN are still emerging, the evidence revealed an aberrant level of gasotransmitters in patients with diabetes. In studies, different gasotransmitter donors have been implicated in ameliorating diabetic renal dysfunction. In this perspective, we summarized an overview of the recent advances in the physiological relevance of the gaseous molecules and their multifaceted interaction with other potential factors, such as extracellular matrix (ECM), in the severity modulation of DN. Moreover, the perspective of the present review highlights the possible therapeutic interventions of gasotransmitters in ameliorating this dreaded disease.
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Affiliation(s)
- Subir Kumar Juin
- Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
- Department of Microbiology & Immunology, Brown Cancer Center, Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Rosemary Ouseph
- Division of Nephrology & Hypertension, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Dibson Dibe Gondim
- Department of Pathology, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Venkatakrishna Rao Jala
- Department of Microbiology & Immunology, Brown Cancer Center, Center for Microbiomics, Inflammation and Pathogenicity, University of Louisville School of Medicine, Louisville, KY 40202, USA
| | - Utpal Sen
- Department of Physiology, University of Louisville School of Medicine, Louisville, KY 40202, USA
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Pan M, Guan Z, Reinach PS, Kang L, Cao Y, Zhou D, Srinivasalu N, Zhao F, Qu J, Zhou X. PPARγ modulates refractive development and form deprivation myopia in Guinea pigs. Exp Eye Res 2020; 202:108332. [PMID: 33152389 DOI: 10.1016/j.exer.2020.108332] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/26/2022]
Abstract
Form deprivation myopia (FDM) is characterized by loss of choroidal thickness (ChT), reduced choroidal blood perfusion (ChBP), and consequently scleral hypoxia. In some tissues, changes in levels of peroxisome proliferator-activated receptor γ (PPARγ) expression modulate hypoxia-induced pathological responses. We determined if PPARγ modulates FDM through changes in ChT, ChBP, scleral hypoxia-inducible transcription factor (HIF-1α) that in turn regulate scleral collagen type 1 (COL1) expression levels in guinea pigs. Myopia was induced by occluding one eye, while the fellow eye served as control. They received daily peribulbar injections of either the PPARγ antagonist GW9662, or the GW1929 agonist, with or without ocular occlusion for 4 weeks. Ocular refraction and biometric parameters were estimated at baseline, 2 and 4 weeks post-treatment. ChT and ChBP were measured at the 2- and 4-week time points. Western blot analysis determined the expression levels of scleral HIF-1α and COL1. GW9662 induced a myopic shift in unoccluded eyes. Conversely, GW1929 inhibited FDM progression without affecting the refraction in unoccluded eyes. GW9662 reduced both ChT and ChBP in unoccluded eyes, while GW1929 inhibited their declines in occluded eyes. Scleral HIF-1α expression rose in GW9662-treated unoccluded eyes whereas GW1929 reduced HIF-1α upregulation in occluded eyes. GW9662 downregulated scleral COL1 expression in unoccluded eyes, while GW1929 reduced their decreases in occluded eyes. Therefore, PPARγ modulates collagen expression levels and FDM through an inverse relationship between changes in PPARγ and HIF-1α expression levels.
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Affiliation(s)
- Miaozhen Pan
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Zhenqi Guan
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Peter S Reinach
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Lin Kang
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Yuqing Cao
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Dengke Zhou
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Nethrajeith Srinivasalu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Fei Zhao
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China
| | - Jia Qu
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China.
| | - Xiangtian Zhou
- School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China; State Key Laboratory of Optometry, Ophthalmology, and Vision Science, Wenzhou, Zhejiang, China; Research Unit of Myopia Basic Research and Clinical Prevention and Control, Chinese Academy of Medical Sciences (2019RU025), China.
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Ahmed OAA, El-Bassossy HM, Azhar AS, Tarkhan MM, El-Mas MM. Interference with AGEs formation and AGEs-induced vascular injury mediates curcumin vascular protection in metabolic syndrome. Sci Rep 2020; 10:315. [PMID: 31941978 PMCID: PMC6962217 DOI: 10.1038/s41598-019-57268-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 12/23/2019] [Indexed: 12/15/2022] Open
Abstract
Vascular dysfunction predisposes to cardiovascular complications of metabolic syndrome (MetS). The current study investigated the mechanism(s) of curcumin's (CUR) protective effect against vascular reactivity irregularities in MetS. MetS was induced by feeding rats on high fructose high salt diet. Tension studies were undertaken in aortic rings to assess the influence of CUR on vasoconstrictor or vasorelaxant responses. The effect on advanced glycation endproducts (AGEs) was studied by incubating aortic tissues with methylglyoxal, the AGEs precursor, in the absence and presence of CUR. In addition, CUR effects on in-vitro generation of AGEs and diphenyl-2-picrylhydrazyl (DPPH) free radicals were studied. The incubation with CUR for 1 hr produced significant and concentration-dependent alleviation of the exaggerated vasoconstriction observed in aortas isolated from MetS, however failed to improve the concomitant attenuation of vasodilatory responses to ACh in PE-precontracted aortas. By contrast, CUR caused direct concentration-dependent vasodilations of precontracted aortas, effects that were blunted after nitric oxide synthase inhibition by L-NAME. Similar to its effects in MetS aortas, CUR alleviated exaggerated PE vasoconstriction but did not affect impaired ACh vasodilations in AGEs-exposed aortas. In addition, CUR showed significant dose-dependent DPPH free radicals scavenging activity and inhibited both MG and fructose induced AGEs formation at the level of protein oxidation step as evident from the effect on dityrosine and N-formylkyramine. CUR alleviates exaggerated vasoconstriction in MetS through interfering with AGEs formation and AGEs-induced vascular injury. Free radical scavenging and direct vasodilatory activities could also participate in the advantageous vascular actions of CUR.
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Affiliation(s)
- Osama A A Ahmed
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah, KSA, Saudi Arabia. .,Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Minia University, Minia, Egypt.
| | - Hany M El-Bassossy
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt
| | - Ahmad S Azhar
- Pediatric Cardiac Center of Excellence, Faculty of Medicine, King Abdulaziz University, Jeddah, KSA, Saudi Arabia
| | - Mayada M Tarkhan
- Department of Biochemistry, Faculty of Science, King Abdulaziz University, Jeddah, KSA, Saudi Arabia
| | - Mahmoud M El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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Ibrahim KS, El-Yazbi AF, El-Gowelli HM, El-Mas MM. Heme oxygenase byproducts variably influences myocardial and autonomic dysfunctions induced by the cyclosporine/diclofenac regimen in female rats. Biomed Pharmacother 2018; 101:889-897. [DOI: 10.1016/j.biopha.2018.03.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 03/04/2018] [Accepted: 03/06/2018] [Indexed: 12/15/2022] Open
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El-Yazbi AF, Eid AH, El-Mas MM. Cardiovascular and renal interactions between cyclosporine and NSAIDs: Underlying mechanisms and clinical relevance. Pharmacol Res 2018; 129:251-261. [DOI: 10.1016/j.phrs.2017.11.029] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/10/2017] [Accepted: 11/22/2017] [Indexed: 12/20/2022]
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Helmy MM, Helmy MW, El-Mas MM. Additive Renoprotection by Pioglitazone and Fenofibrate against Inflammatory, Oxidative and Apoptotic Manifestations of Cisplatin Nephrotoxicity: Modulation by PPARs. PLoS One 2015; 10:e0142303. [PMID: 26536032 PMCID: PMC4633146 DOI: 10.1371/journal.pone.0142303] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 10/19/2015] [Indexed: 01/06/2023] Open
Abstract
Nephrotoxicity is a major side effect for the antineoplastic drug cisplatin. Here, we employed pharmacological, biochemical, and molecular studies to investigate the role of peroxisome proliferator-activated receptors (PPARs) in cisplatin nephrotoxicity. Rats were treated with a single i.p. dose of cisplatin (5 mg/kg) alone or combined with pioglitazone (PPARγ agonist), fenofibrate (PPARα agonist), pioglitazone plus fenofibrate, or thalidomide (Tumor necrosis factor-α inhibitor; TNF-α). Cisplatin nephrotoxicity was evidenced by rises in renal indices of functional (blood urea nitrogen, BUN, and creatinine), inflammatory (TNF-α, interleukin 6, IL-6), oxidative (increased malondialdehyde, MDA, and decreased superoxide dismutase, SOD and nitric oxide metabolites, NOx), apoptotic (caspase 3), and histological (glomerular atrophy, acute tubular necrosis and vacuolation) profiles. Cisplatin effects were partly abolished upon concurrent exposure to pioglitazone, fenofibrate, or thalidomide; more renoprotection was observed in rats treated with pioglitazaone plus fenofibrate. Immunostaining showed that renal expressions of PPARα and PPARγ were reduced by cisplatin and restored to vehicle-treated values after simultaneous treatment with pioglitazone or fenofibrate. Fenofibrate or pioglitazone renoprotection remained unaltered after concurrent blockade of PPARα (GW6471) and PPARγ (GW9662), respectively. To complement the rat studies, we also report that in human embryonic kidney cells (HEK293 cells), increases caused by cisplatin in inflammatory, apoptotic, and oxidative biomarkers were (i) partly improved after exposure to pioglitazone, fenofibrate, or thalidomide, and (ii) completely disappeared in cells treated with a combination of all three drugs. These data establish that the combined use of pioglitazone and fenofibrate additively improved manifestations of cisplatin nephrotoxicity through perhaps GW6471/GW9662-insensitive mechanisms.
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Affiliation(s)
- Mai M Helmy
- Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Maged W Helmy
- Pharmacology and Toxicology, Faculty of Pharmacy, Damanhour University, Damanhour, Egypt
| | - Mahmoud M El-Mas
- Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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Pioglitazone ameliorates methotrexate-induced renal endothelial dysfunction via amending detrimental changes in some antioxidant parameters, systemic cytokines and Fas production. Vascul Pharmacol 2015; 74:139-150. [DOI: 10.1016/j.vph.2015.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/29/2015] [Accepted: 07/04/2015] [Indexed: 02/07/2023]
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Fouda MA, El-Gowelli HM, El-Gowilly SM, Rashed L, El-Mas MM. Impairment of nitric oxide synthase but not heme oxygenase accounts for baroreflex dysfunction caused by chronic nicotine in female rats. PLoS One 2014; 9:e98681. [PMID: 24870610 PMCID: PMC4037226 DOI: 10.1371/journal.pone.0098681] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Accepted: 05/07/2014] [Indexed: 12/31/2022] Open
Abstract
We recently reported that chronic nicotine impairs reflex chronotropic activity in female rats. Here, we sought evidence to implicate nitric oxide synthase (NOS) and/or heme oxygenase (HO) in the nicotine-baroreflex interaction. Baroreflex curves relating changes in heart rate to increases (phenylephrine) or decreases (sodium nitroprusside) in blood pressure were generated in conscious female rats treated with nicotine or saline in absence and presence of pharmacological modulators of NOS or HO activity. Compared with saline-treated rats, nicotine (2 mg/kg/day i.p., for 14 days) significantly reduced the slopes of baroreflex curves, a measure of baroreflex sensitivity (BRS). Findings that favor the involvement of NOS inhibition in the nicotine effect were (i) NOS inhibition (Nω-Nitro-L-arginine methyl ester, L-NAME) reduced BRS in control rats but failed to do so in nicotine-treated rats, (ii) L-arginine, NO donor, reversed the BRS inhibitory effect of nicotine. Alternatively, HO inhibition (zinc protoporphyrin IX, ZnPP) had no effect on BRS in nicotine- or control rats and failed to reverse the beneficial effect of L-arginine on nicotine-BRS interaction. Similar to female rats, BRS was reduced by L-NAME, but not ZnPP, in male rats and the L-NAME effect was not accentuated after concomitant administration of nicotine. Baroreflex dysfunction caused by nicotine in female rats was blunted after supplementation with hemin (HO inducer) but not tricarbonyldichlororuthenium(II) dimer (CORM-2), a carbon monoxide (CO) releasing molecule, or bilirubin, the breakdown product of heme catabolism. The facilitatory effect of hemin was abolished upon simultaneous treatment with L-NAME or 1H-[1], [2], [4] oxadiazolo[4,3-a] quinoxalin-1-one (inhibitor of soluble guanylate cyclase, sGC). The activities of HO and NOS in brainstem tissues were also significantly increased by hemin. Thus, the inhibition of NOS, but not HO, accounts for the baroreflex depressant of chronic nicotine. Further, hemin alleviates the nicotine effect through a mechanism that is NOS/sGC but not CO or bilirubin-dependent.
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Affiliation(s)
- Mohamed A. Fouda
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Hanan M. El-Gowelli
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Sahar M. El-Gowilly
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Laila Rashed
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mahmoud M. El-Mas
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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El-Gowelli HM, Helmy MW, Ali RM, El-Mas MM. Celecoxib offsets the negative renal influences of cyclosporine via modulation of the TGF-β1/IL-2/COX-2/endothelin ET(B) receptor cascade. Toxicol Appl Pharmacol 2014; 275:88-95. [PMID: 24462674 DOI: 10.1016/j.taap.2014.01.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 01/10/2014] [Accepted: 01/12/2014] [Indexed: 12/20/2022]
Abstract
Endothelin (ET) signaling provokes nephrotoxicity induced by the immunosuppressant drug cyclosporine A (CSA). We tested the hypotheses that (i): celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, counterbalances renal derangements caused by CSA in rats and (ii) the COX-2/endothelin ET(B) receptor signaling mediates the CSA-celecoxib interaction. Ten-day treatment with CSA (20 mg/kg/day) significantly increased biochemical indices of renal function (serum urea, creatinine), inflammation (interleukin-2, IL-2) and fibrosis (transforming growth factor-β₁, TGF-β₁). Histologically, CSA caused renal tubular atrophy along with interstitial fibrosis. These detrimental renal effects of CSA were largely reduced in rats treated concurrently with celecoxib (10 mg/kg/day). We also report that cortical glomerular and medullary tubular protein expressions of COX-2 and ET(B) receptors were reduced by CSA and restored to near-control values in rats treated simultaneously with celecoxib. The importance of ET(B) receptors in renal control and in the CSA-celecoxib interaction was further verified by the findings (i) most of the adverse biochemical, inflammatory, and histopathological profiles of CSA were replicated in rats treated with the endothelin ETB receptor antagonist BQ788 (0.1 mg/kg/day, 10 days), and (ii) the BQ788 effects, like those of CSA, were alleviated in rats treated concurrently with celecoxib. Together, the data suggest that the facilitation of the interplay between the TGF-β1/IL-2/COX-2 pathway and the endothelin ET(B) receptors constitutes the cellular mechanism by which celecoxib ameliorates the nephrotoxic manifestations of CSA in rats.
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Affiliation(s)
- Hanan M El-Gowelli
- Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Maged W Helmy
- Pharmacology and Toxicology, Faculty of Pharmacy, Pharos University, Alexandria, Egypt
| | - Rabab M Ali
- Pharmacology and Toxicology, Faculty of Pharmacy, Pharos University, Alexandria, Egypt
| | - Mahmoud M El-Mas
- Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt.
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El-Gowelli HM, El-Gowilly SM, Elsalakawy LK, El-Mas MM. Nitric oxide synthase/K+ channel cascade triggers the adenosine A(2B) receptor-sensitive renal vasodilation in female rats. Eur J Pharmacol 2013; 702:116-25. [PMID: 23396225 DOI: 10.1016/j.ejphar.2013.01.049] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 01/17/2013] [Accepted: 01/29/2013] [Indexed: 01/02/2023]
Abstract
Adenosine A2B-receptors mediate the adenosine-evoked renal vasodilations in male rats. Here, we tested whether this finding could be replicated in female renal vasculature and whether K(+) hyperpolarization induced by nitric oxide synthase (NOS) and/or heme oxygenase (HO) accounts for adenosine A2B receptor-sensitive renal vasodilations. In phenylephrine-preconstricted perfused kidneys, vasodilations caused by the adenosine analog 5'-N-ethylcarboxamidoadenosine (NECA, 1.6-50 nmol) were attenuated after blockade of adenosine A2B (alloxazine) but not A2A [8-(3-Chlorostyryl) caffeine, CSC] or A3 receptors (N-(2-methoxyphenyl)-N'-[2-(3-pyridinyl)-4-quinazolinyl]-urea, VUF 5574), confirming the preferential involvement of A2B receptors in NECA responses. NOS activation mediated the A2B receptor-mediated NECA response because: (i) NOS inhibition (N(ω)-nitro-L-arginine-methyl ester, L-NAME) attenuated NECA vasodilations, (ii) concurrent L-NAME/alloxazine exposure caused more inhibition of NECA responses, and (iii) inhibition of NECA responses by alloxazine disappeared in L-arginine-supplemented preparations. Although HO inhibition (zinc protoporphyrin) failed to modify NECA responses, the attenuation of these responses by alloxazine disappeared in hemin (HO inducer)-treated preparations. NECA vasodilations were also attenuated after exposure to BaCl2, glibenclamide but not tetraethylammonium (blockers of inward rectifier, ATP-sensitive, and Ca(2+)-dependent K(+)-channels, respectively). The combined alloxazine/BaCl2/glibenclamide infusion caused no additional attenuation of NECA vasodilations. Vasodilations caused by minoxidil (K(+)-channel opener) were reduced by L-NAME or BaCl2/glibenclamide, supporting the importance of NOS signaling in K(+) hyperpolarization. NECA or minoxidil vasodilations were attenuated by ouabain, Na(+)/K(+)-ATPase inhibitor, and in KCl-preconstricted preparations. Overall, facilitation of adenosine A2B receptor/NOS/K(+) channel/Na(+)/K(+)-ATPase cascade underlies NECA vasodilations in female rats. Enhancing HO activity, albeit not causally related to NECA vasodilations, improves the pharmacologically compromised (alloxazine) NECA response.
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Affiliation(s)
- Hanan M El-Gowelli
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
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