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Showing 3 results for Naeimi

Vahid Khori, Samaneh Naeimipour, Alimohammad Alizadeh, Ali Haeri Rouhani, Mona Pourabouk, Fakhri Badaghabadi, Maryam Rajaei, Sepideh Shariatnezhad, Hamidreza Moheimani, Saeed Saleki, Mohammad Ali Zeyghami, Mohsen Nayebpour,
Volume 15, Issue 4 (Winter 2012)
Abstract

Introduction: Previous studies have indicated a relationship between MPTP pore and AV nodal rate-dependent properties. The aim of present study was to determine acute direct effects of cyclosporine on extracellular field potential of isolated rabbit AV node during experimental atrial fibrillation. Methods: In one group of male New Zealand rabbits (1.5-2.5 kg) cumulative concentrations of cyclosporine (0.5 – 10 m) were applied on isolated perfused atrio-nodal preparation (n=7). Extracellular field potential recording was sampled during specific stimulation protocols (recovery, zone of concealment and atrial fibrillation) in the presence of drug on electrophysiological properties of AV-node. Results: Cyclosporine significantly decreased the ventricular rate (HH mean) from 231.8 ± 5.7 to 277.4 ± 14.6 msec and functional refractory period during AF (AF FRP) from 138.3 ± 7.5 to 161.2 ± 10.31 msec in control and treated groups, respectively. Effective refractory period during AF (AF ERP) was significantly decreased by cyclosporine 10 mM compared to control group (p<0.05). Conclusion: Cyclosporine-evoked slowing ventricular heart rate during AF was induced by increasing functional refractoy period and ZOC. A possible mechanism can be through blocking of MPT pores.
Vahid Khori, Samaneh Naeimipour, Ali-Mohammad Alizadeh, Mona Pourabouk, Fakhri Badaghabadi, Maryah Rajaei, Sepideh Shariatnezhad, Hamidreza Moheimani, Saeed Saleki, Mohammadali Zeyghami, Mohsen Nayebpour,
Volume 16, Issue 1 (Spring 2012)
Abstract

Introduction: Intranodal pathways of atrioventricular (AV) node play a vital role in the delay of conduction time in response to various atrial inputs. The present study was aimed to determine the frequency-dependent electrophysiological properties of concealed slow pathway according to a functional model of isolated rabbit atrioventricular node preparation after fast pathway ablation. Methods: Experiments were carried out in rabbit isolated heart AV-nodal preparations (N=8) by superfused/perfused mode. Extracellular recording was carried out from transitional cells of posterior and anterior extension of AV-node and upper part of atrium and its bundle. Unipolar silver electrode (100 μm) and direct voltage (100-110 V) was applied to create AV-nodal fast pathway ablation. Results: Minimum conduction time (AHmin) was significantly increased after fast pathway ablation (p<0.05). Fast pathway ablation had no significant impact on fatigue phenomenon but significantly reduced facilitation value (p<0.05). Rate-dependency properties of concealed slow pathway were explained according to functional nodal model. Conclusion: The mathematical functional model accurately simulated frequency-dependent electrophysiological properties of concealed slow pathway after fast pathway ablation, but some modifications are necessary for accurate prediction of nodal behavior in various cycle lengths and in arrhythmia. Concealed slow pathway may be considered as a potential electrophysiological substrate of fatigue and facilitation phenomenon
Reza Naeimi, Maryam Ghasemi-Kasman, Sohrab Kazemi, Manouchehr Ashrafpour, Ali Akbar Moghadamnia, Fereshteh Pourabdolhossein,
Volume 22, Issue 2 (June 2018)
Abstract

Introduction: Recently, herbal medicine is widely used as an alternative and complementary therapy in several neurological disorders such as epilepsy. The anti-inflammatory and neuroprotective effects of Zingiber officinale or ginger have been well-documented. The present study was designed to evaluate the effects of ginger extract pre-treatment on seizures behavior, neuronal density and astrocytes activation in pentylenetetrazol (PTZ)- induced kindling model. Methods: Kindling model was induced in mice by repetitive administration of PTZ at sub convulsive dose. Hydroalcoholic extract of ginger at doses of 25, 50 or 100 mg/kg were daily injected 10 days before PTZ injections and intraperitoneal administration of extract was continued 1h before each PTZ injection. Immunostaining against NeuN and GFAP as neuronal and astrocyte markers, respectively, was carried out on brain tissue sections. Results: Our data showed that ginger extract pre-treatment, especially at dose of 100 mg/kg, reduced the seizures behavior in PTZ receiving animals. Immunostaining against NeuN biomarker demonstrated that neuronal death was alleviated in animals under treatment of ginger extract. Furthermore, application of ginger extract attenuated the number of GFAP expressing cells in hippocampus of fully-kindled animals. Conclusion: Overall, our data suggest that ginger pre-treatment exerts significant neuroprotective effect by attenuation of astrocytes activation in PTZ-induced kindling model. It can be concluded that ginger might be used as effective supplementary agent in epileptic patients.



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