Canadian journal of physiology and pharmacology
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Can. J. Physiol. Pharmacol. · Sep 2012
The acutely occluded left main coronary artery culprit in cardiogenic shock and initial percutaneous coronary intervention: a substudy of the Manitoba "no option" left main PCI registry.
We aim to describe the in-hospital outcomes of the first reported Canadian cohort of patients with cardiogenic shock and acute myocardial infarction (MI) due to acute and total occlusion of the left main coronary artery, treated with initial percutaneous coronary intervention (PCI). Acute left main thromboses with cardiogenic shock were identified (N = 8) from a retrospective consecutive cohort of high risk left main PCI (N = 56) performed at our institution from 2004-2009. The mean age was 62.3 ± 13.2 years, with 6 (75%) male patients. ⋯ In-hospital mortality occurred in 3 patients (38%). Acute left main occlusion is a rare but devastating presentation of myocardial infarction, invariably with cardiogenic shock. Emergent PCI may be an effective method to acutely revascularize this subset of patients; however, aggressive post-PCI care including ECMO, CABG, and ventricular support may be required to improve patient survival.
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Can. J. Physiol. Pharmacol. · Jul 2012
Mepivacaine-induced contraction is attenuated by endothelial nitric oxide release in isolated rat aorta.
Mepivacaine is an aminoamide-linked local anesthetic with an intermediate duration that intrinsically produces vasoconstriction both in vivo and in vitro. The aims of this in-vitro study were to examine the direct effect of mepivacaine in isolated rat aortic rings and to determine the associated cellular mechanism with a particular focus on endothelium-derived vasodilators, which modulate vascular tone. In the aortic rings with or without endothelium, cumulative mepivacaine concentration-response curves were generated in the presence or absence of the following antagonists: N(ω)-nitro-L-arginine methyl ester [L-NAME], indomethacin, fluconazole, methylene blue, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one [ODQ], verapamil, and calcium-free Krebs solution. ⋯ Indomethacin slightly attenuated mepivacaine-induced contraction, whereas verapamil and calcium-free Krebs solution more strongly attenuated this contraction. The vasoconstriction induced by mepivacaine is attenuated mainly by the endothelial nitric oxide - cyclic guanosine monophosphate pathway. In addition, mepivacaine-induced contraction involves cyclooxygenase pathway activation and extracellular calcium influx via voltage-operated calcium channels.
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Can. J. Physiol. Pharmacol. · Apr 2012
Antinociceptive and anti-inflammatory effects of electroacupuncture on experimental arthritis of the rat temporomandibular joint.
This study investigated the antinociceptive and anti-inflammatory effects of electroacupuncture (EA) on zymosan-induced acute arthritis of the rat temporomandibular joint (TMJ). Male Wistar rats were injected with saline or zymosan (control group; 2 mg) into the left TMJ. Low frequency EA (10 Hz, 30 min) was performed at acupoints (LI4, LI11, ST36, ST44) or sham points 2 h after or 1 h before zymosan administration. ⋯ The results showed that EA inhibited inflammatory parameters such as neutrophil migration, vascular permeability, and tumour necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) expression in the TMJ compared with the sham group (p < 0.05). Histopathological analysis showed that EA significantly inhibited edema and periarticular infiltration (p < 0.05) compared with the control and sham groups. EA at acupoints produced antinociceptive and anti-inflammatory effects on zymosan-induced arthritis in the rat TMJ.
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Can. J. Physiol. Pharmacol. · Feb 2012
Endothelin-1 induces neutrophil recruitment in adaptive inflammation via TNFα and CXCL1/CXCR2 in mice.
Endothelin mediates neutrophil recruitment during innate inflammation. Herein we address whether endothelin-1 (ET-1) is involved in neutrophil recruitment in adaptive inflammation in mice, and its mechanisms. Pharmacological treatments were used to determine the role of endothelin in neutrophil recruitment to the peritoneal cavity of mice challenged with antigen (ovalbumin) or ET-1. ⋯ The ET-1- and ovalbumin-induced neutrophil recruitment were reduced in TNFR1 deficient mice, and by treatments targeting CXCL1 or CXC chemokine receptor 2 (CXCR2); further, treatment with bosentan, BQ-123, or BQ-788 inhibited ET-1- and antigen-induced production of TNFα and CXCL1. Furthermore, ET-1 and ovalbumin challenge induced an increase in the number of cells expressing the Gr1(+) markers in the granulocyte gate, CD11c(+) markers in the monocyte gate, and CD4(+) and CD45(+) (B220) markers in the lymphocyte gate in an ET(A)- and ET(B)-dependent manner, as determined by flow cytometry analysis, suggesting that ET-1 might be involved in the recruitment of neutrophils and other cells in adaptive inflammation. Therefore, the present study demonstrates that ET-1 is an important mediator for neutrophil recruitment in adaptive inflammation via TNFα and CXCL1/CXCR2-dependent mechanism.
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Can. J. Physiol. Pharmacol. · Jan 2012
Clinical TrialMechanisms involved in the differential reduction of omega-3 and omega-6 highly unsaturated fatty acids by structural heart disease resulting in "HUFA deficiency".
The causes of reduced levels of omega-3 and omega-6 highly unsaturated fatty acids ("HUFA deficiency") in heart failure remain unresolved. HUFA profiles were examined in the serum of 331 patients with failing versus nonfailing heart disease. Arachidonic acid was positively correlated (P < 0.001) with eicosapentaenoic acid (EPA) (r = 0.40) and docosahexaenoic acid (DHA) (r = 0.53) and negatively with palmitic (r = 0.42), palmitoleic (r = 0.38), and oleic acid (r = 0.48). ⋯ Equidirectional but less pronounced effects on HUFA were induced by sympathetic activation and (or) insulin resistance (fat and sugar fed to deoxycorticosterone acetate (DOCA)-salt rats) but not by compensated cardiac overload alone (DOCA-salt or aortic constriction), or reduced fatty acid oxidation (CPT-1 inhibition). Based on administration of omega-3 HUFA (OMACOR), dilatation is identified as a target for 1-2 g omega-3 HUFA·day(-1). Interventions for reduced arachidonic acid remain to be explored.