The Experts below are selected from a list of 2046 Experts worldwide ranked by ideXlab platform

Brant E Isakson - One of the best experts on this subject based on the ideXlab platform.

  • Endothelial Cell Transfection of ex vivo Arteries
    2016
    Co-Authors: Alexander W. Lohman, Brant E Isakson, Adam C Straub, To Brant, E. Isakson, Robert Berne M. Cardiovascular
    Abstract:

    Abstract: The vascular endothelium plays an essential role in regulating Blood Vessel Tone, Blood flow and Blood pressure. Current vascular model systems for examination of endothelial cell biology and Blood Vessel physiology and pathology rely on cell culture and the generation of genetically modified animals. While these systems are advantageous for studying the endothelium, many cell culture models omit the contribution of other cells types present in the native Blood Vessel wall and the generation of genetically modified animals can be costly and time consuming. The following protocol outlines a novel ex vivo endothelial cell transfection for the knockdown of endogenously expressed endothelial cell proteins in intact isolated arteries. Briefly, arteries are isolated from the mouse and the lumen is perfused with siRNA and Nucleofector ™ transfection reagent. The artery is then ligated at both ends and briefly electroporated to introduce the siRNA specifically into the endothelial cells, followed by perfusion of the lumen to flush excess siRNA. Transfected arteries are then cultured 18-24 hours for knockdown of targeted proteins. This system provides the utility of selectively knocking down a protein(s) of interest specifically from the vascular endothelium, providing the advantages of a genetically modified animal without the long time frame required for generation of tissue specific knockout animals. This protocol requires approximately 1 hour from isolation of the artery from the mouse to culturing of the transfecte

  • Mechanisms of ATP release and signalling in the Blood Vessel wall
    Cardiovascular research, 2012
    Co-Authors: Alexander W. Lohman, Marie Billaud, Brant E Isakson
    Abstract:

    The nucleotide adenosine 5′-triphosphate (ATP) has classically been considered the cell's primary energy currency. Importantly, a novel role for ATP as an extracellular autocrine and/or paracrine signalling molecule has evolved over the past century and extensive work has been conducted to characterize the ATP-sensitive purinergic receptors expressed on almost all cell types in the body. Extracellular ATP elicits potent effects on vascular cells to regulate Blood Vessel Tone but can also be involved in vascular pathologies such as atherosclerosis. While the effects of purinergic signalling in the vasculature have been well documented, the mechanism(s) mediating the regulated release of ATP from cells in the Blood Vessel wall and circulation are now a key target of investigation. The aim of this review is to examine the current proposed mechanisms of ATP release from vascular cells, with a special emphasis on the transporters and channels involved in ATP release from vascular smooth muscle cells, endothelial cells, circulating red Blood cells, and perivascular sympathetic nerves, including vesicular exocytosis, plasma membrane F1/F0-ATP synthase, ATP-binding cassette (ABC) transporters, connexin hemichannels, and pannexin channels.

David J Beech - One of the best experts on this subject based on the ideXlab platform.

Karen A Matthews - One of the best experts on this subject based on the ideXlab platform.

  • interactions between autonomic nervous system activity and endothelial function a model for the development of cardiovascular disease
    Psychosomatic Medicine, 2004
    Co-Authors: Kelly F Harris, Karen A Matthews
    Abstract:

    Objectives Endothelial dysfunction is a new pathway in cardiovascular disease (CVD) development. Psychosocial factors have been little studied in relation to endothelial function, although they may interact via associations with the autonomic nervous system (ANS). The purpose of this review is to propose a model by which psychosocial factors are related to CVD development through interactions between the ANS and vascular endothelium. Methods The literature supporting an interaction between the ANS and endothelium in healthy and disease states is reviewed. Potential mechanisms linking the two systems are explored as a pathway for CVD development. Results Endothelial dysfunction and impaired cardiovascular ANS regulation are both markers for increased CVD risk. Sympathetic nerves and vascular endothelial cells share a functional antagonism in healthy states to maintain appropriate Blood Vessel Tone. Alterations in sympathetic activity and endothelial cell function are both observed early in the development of CVD and may result from an inability to maintain the functional antagonism. Impairments in either ANS regulation or endothelial function may contribute to further disease development by evoking maladaptive changes in the opposing system. Conclusions Although interactions between cardiovascular ANS regulation and endothelial function are likely involved in CVD development, further research is needed to determine whether ANS and endothelium interactions are a plausible pathway linking psychosocial factors with increased CVD risk.

B Silke - One of the best experts on this subject based on the ideXlab platform.

  • nitric oxide modulation of Blood Vessel Tone identified by arterial waveform analysis
    Clinical Science, 2001
    Co-Authors: Gary E Mcveigh, Patrick Allen, David R Morgan, Colm G Hanratty, B Silke
    Abstract:

    : Traditionally, nitric oxide-mediated alteration in Blood Vessel Tone has been inferred from changes in flow in response to physical and pharmacological interventions using plethysmographic or ultrasonic techniques. We hypothesized that alteration in pulsatile arterial function may represent a more sensitive measure to detect and monitor nitric oxide-mediated modulation of arterial smooth muscle Tone. Healthy male volunteers (n = 15) had radial artery pressure pulse waveforms recorded using a calibrated tonometer device. A computer-based assessment of the diastolic pressure decay was employed to quantify changes in arterial waveform morphology in terms of altered pulsatile (arterial compliance) and steady-state (peripheral resistance) haemodynamics. N(G)-nitro-L-arginine methyl ester (L-NAME), a stereospecific inhibitor of nitric oxide synthesis, was infused intravenously in incrementally increasing doses of 0.25, 0.5 and 0.75 mg/kg for 8 min each. Subjects then received either L-arginine or D-arginine (200 mg/kg over 15 min) intravenously in a blinded fashion. On a separate day, subjects had radial artery pressure pulse waveforms recorded before and after the sublingual administration of glyceryl trinitrate, an exogenous donor of nitric oxide. Cardiac output and heart rate decreased and mean arterial Blood pressure increased significantly (P < 0.01 for all) in response to the incremental intravenous infusion of L-NAME. Small artery compliance decreased, whereas systemic vascular resistance increased in response to nitric oxide synthesis inhibition (P < 0.01 for both). The intravenous infusion of L-arginine restored the pulsatile and steady-state haemodynamic parameters to pre-treatment values, whereas D-arginine had no effect. Sublingual glyceryl trinitrate decreased systemic vascular resistance by 11%, whereas large artery- and small artery-compliance increased by 25% and 44% respectively. Pressure pulse contour analysis represents a sensitive and convenient technique capable of tracking changes in the pulsatile function of arteries accompanying nitric oxide-mediated alteration in arterial smooth muscle Tone.

Alexander W. Lohman - One of the best experts on this subject based on the ideXlab platform.

  • Endothelial Cell Transfection of ex vivo Arteries
    2016
    Co-Authors: Alexander W. Lohman, Brant E Isakson, Adam C Straub, To Brant, E. Isakson, Robert Berne M. Cardiovascular
    Abstract:

    Abstract: The vascular endothelium plays an essential role in regulating Blood Vessel Tone, Blood flow and Blood pressure. Current vascular model systems for examination of endothelial cell biology and Blood Vessel physiology and pathology rely on cell culture and the generation of genetically modified animals. While these systems are advantageous for studying the endothelium, many cell culture models omit the contribution of other cells types present in the native Blood Vessel wall and the generation of genetically modified animals can be costly and time consuming. The following protocol outlines a novel ex vivo endothelial cell transfection for the knockdown of endogenously expressed endothelial cell proteins in intact isolated arteries. Briefly, arteries are isolated from the mouse and the lumen is perfused with siRNA and Nucleofector ™ transfection reagent. The artery is then ligated at both ends and briefly electroporated to introduce the siRNA specifically into the endothelial cells, followed by perfusion of the lumen to flush excess siRNA. Transfected arteries are then cultured 18-24 hours for knockdown of targeted proteins. This system provides the utility of selectively knocking down a protein(s) of interest specifically from the vascular endothelium, providing the advantages of a genetically modified animal without the long time frame required for generation of tissue specific knockout animals. This protocol requires approximately 1 hour from isolation of the artery from the mouse to culturing of the transfecte

  • Mechanisms of ATP release and signalling in the Blood Vessel wall
    Cardiovascular research, 2012
    Co-Authors: Alexander W. Lohman, Marie Billaud, Brant E Isakson
    Abstract:

    The nucleotide adenosine 5′-triphosphate (ATP) has classically been considered the cell's primary energy currency. Importantly, a novel role for ATP as an extracellular autocrine and/or paracrine signalling molecule has evolved over the past century and extensive work has been conducted to characterize the ATP-sensitive purinergic receptors expressed on almost all cell types in the body. Extracellular ATP elicits potent effects on vascular cells to regulate Blood Vessel Tone but can also be involved in vascular pathologies such as atherosclerosis. While the effects of purinergic signalling in the vasculature have been well documented, the mechanism(s) mediating the regulated release of ATP from cells in the Blood Vessel wall and circulation are now a key target of investigation. The aim of this review is to examine the current proposed mechanisms of ATP release from vascular cells, with a special emphasis on the transporters and channels involved in ATP release from vascular smooth muscle cells, endothelial cells, circulating red Blood cells, and perivascular sympathetic nerves, including vesicular exocytosis, plasma membrane F1/F0-ATP synthase, ATP-binding cassette (ABC) transporters, connexin hemichannels, and pannexin channels.