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PubMed2000

Temporal relation between acoustic and force responses at the adductor pollicis during nondepolarizing neuromuscular block.

BACKGROUND: Contracting muscle emits sounds. The purpose of this study was to compare the time course of muscular paralysis at the adductor pollicis muscle (AP) with use of acoustic myography and mechanomyography. METHODS: Thirteen elective surgery patients, American Society of Anesthesiologists physical status I, received rocuronium (0.6 mg/kg intravenously) as a bolus dose during general anesthesia. Force of AP was measured with use of a strain gauge, and sounds were recorded simultaneously with use of a small condenser microphone fixed on the palmar surface of the hand over the AP. Supramaximal stimulation was applied to the ulnar nerve at 0.1 Hz for 45-60 min. In seven patients, the response to train-of-four stimulation was also recorded during recovery. RESULTS: Force and sounds both were equally sensitive in measuring maximum block. The relation between sound and force was curvilinear, with good agreement near 0 and 100% and acoustic response exceeding mechanical response at intermediate levels of block. The acoustic signal had a slower onset and a faster recovery than the force response. The fade response of sound to train-of-four stimulation also recovered faster than that of force. CONCLUSION: Acoustic myography is an alternative method to monitor muscular paralysis that is easy to set up and applicable to most superficial muscles. However, the time course of relaxation at AP using acoustic myography differs from the time course of force relaxation. Therefore, these two methods are not equivalent when applied to AP.

Adult↗
PubMed1976

Automatic recording and evaluation of neuronography.

The introduction in the 60' s of the Nerve Excitability Test (NET) by Laumans and Jongkees for the diagnosis of Bell's palsy stimulated an interest of quantitative testing of the facial nerve. In 1970 Yanagihara reported the Evoced Myography (EMG; i.e. NET is combined with EMG). Starting with electrophysiological basis of the impulse spread of peripheral nerves May, in 1971, extended this concept by including supraliminal stimuli, i.e. Maximal Stimulation Test (MST), for diagnostic purposes. This method eventually developed into what is known as neuronography (Esslen, Huffmann, Ehrenberger, Satoh). It is undoubtedly a refinement in the question of prognosis of Bell's palsy. Continuing the original concept of May we have developed an electronic device with which to carry out automatically the neuronography that demonstrates an evaluation on a numeric display. We use the conventional bipolar negative square wave for a 1 ms stimulation. We stimulate the angle of the mandible, where the ramus marginalis can be readily found in all patients. Neuronography and Evoked Myography provide earlier a more precise prognosis of facial palsy than Nerve Excitability Test (NET). We developed an electronic device for the Maximal Stimulation Test (MST) of May, M., that is automatic. The device counts the spikes of the evoked myogram. A time window is related to the stimulus to exclude stimulus noise and background muscle noise from the counter. Only spikes seen in this window are processed. The number of spikes generated per stimulus is the measurement of the live axons in a stimulated nerve.

Electronic Data Processing↗
PubMed2005

Remodeling of myometrial radial arteries in preeclampsia.

OBJECTIVE: This study was undertaken to test for structural differences between myometrial radial arteries isolated from women having normal pregnancies and pregnancies complicated by preeclampsia and intrauterine growth restriction. STUDY DESIGN: Pressure myography was used to study myometrial radial arteries obtained at cesarean section. With the use of a transilluminating system, lumen diameter, wall thickness, wall/lumen ratio, distensibility and stress-strain relationship were studied through a range of pressures. Arteries were then fixed in glutaraldehyde, embedded in resin, cross-sectioned, and studied in greater detail by light and electron microscopy. RESULTS: Pressure myography showed that arteries from women with preeclampsia had a reduced lumen diameter, thicker wall, and greater wall/lumen ratio compared with vessels isolated from women with normal pregnancy. Light microscopy indicated an identical media content remodeled around a smaller lumen. Electron microscopy indicated enlarged extracellular spaces in the media but no change in myocyte profile size or number. There was no clear evidence of structural changes in myometrial radial arteries isolated from women with intrauterine growth restriction compared with normal pregnancy. No differences in vessel distensibility or stress-strain relationships were detected in complicated pregnancies. CONCLUSION: The changes observed in myometrial radial arteries isolated from women with preeclampsia are due to inward eutrophic remodeling. Alterations in these vessels may contribute to increased uterine vascular resistance in preeclampsia.

Adult↗
PubMed1995

EMG before and after cervical anterior discectomy.

INTRODUCTION: In patients with cervical root syndromes, the relation between clinical findings and EMG results, the value of the registration of the H-reflex latency of the flexor carpi radial muscle (HFCR) and the rate of recovery of EMG abnormalities following surgery are unclear. METHODS: In 68 patients with cervical radicular syndromes caused by intervertebral disc lesions, EMG was made shortly before anterior cervical discectomy and four months later. EMG consisted of needle myography and bilateral determination of the HFCR. RESULTS: Results of HFCR were unrelated to findings on needle myography. Preoperative EMG abnormalities were related to more severe clinical and myelographic findings. A preoperative abnormal HFCR correlated with good clinical outcome. No relation was found between the clinical outcome and EMG-findings during follow-up. CONCLUSION: Determination of HFCR is a useful EMG-test, but further comparison to tendon reflexes is necessary. EMG identifies patients with more severe root lesions, but cannot be used for evaluation of persistent complaints within the first half year following surgery.

Cervical Vertebrae↗
PubMed1998

Streptomycin inhibition of myogenic tone, K+-induced force and block of L-type calcium current in rat cerebral arteries.

1. Streptomycin has been demonstrated to inhibit mechanosensitive conductances in a wide variety of cell types, including muscle. The action of streptomycin on rat cerebral arteries that exhibit pressure-induced myogenic response was investigated. 2. Pressure-induced tone, measured using isobaric myography, in isolated pressurized cerebral arteries was reversibly and concentration-dependently inhibited by streptomycin with an IC50 of 2.6 mM. 3. Isometric K+-induced force, measured using isometric myography, is supported by voltage-gated Ca2+ entry. Streptomycin reversibly and concentration-dependently inhibited isometric force with an IC50 of 1.71 mM. 4. Voltage-gated macroscopic inward Ca2+ channel currents were recorded from freshly isolated rat basilar myocytes. These were reversibly and concentration-dependently inhibited by streptomycin with an IC50 of 1.79 and 0.47 mM when 10 and 1.8 mM CaCl2, respectively, was used as the charge carrier. 5. These data suggest that streptomycin inhibits myogenic tone and K+-induced isometric force largely by blockade of L-type, dihydropyridine-sensitive Ca2+ channels. In conclusion, streptomycin is not useful in the investigation of stretch-activated channels which may underlie the myogenic response of rat small cerebral arteries.

Animals↗
PubMed2006

Alterations in structure and mechanics of resistance arteries from ouabain-induced hypertensive rats.

We have previously described that chronic administration of ouabain induces hypertension and functional alterations in mesenteric resistance arteries. The aim of this study was to analyze whether ouabain treatment also alters the structural and mechanical properties of mesenteric resistance arteries. Wistar rats were treated for 5 wk with ouabain (8.0 microg/day sc). The vascular structure and mechanics of the third-order branches of the mesenteric artery were assessed with pressure myography and confocal microscopy. Total collagen content was determined by picrosirius red staining, collagen I/III was analyzed by Western blot, and elastin was studied by confocal microscopy. Vascular reactivity was analyzed by wire myography. Internal and external diameters and cross-sectional area were diminished, whereas the wall-to-lumen ratio was increased in arteries from ouabain-treated rats compared with controls. In addition, arteries from ouabain-treated rats were stiffer. Ouabain treatment decreased smooth muscle cell number and increased total and I/III collagens in the vascular wall. However, this treatment did not modify adventitia and media thickness, nuclei morphology, elastin structure, and vascular reactivity to norepinephrine and acetylcholine. The present work shows hypotrophic inward remodeling of mesenteric resistance arteries from ouabain-treated rats that seems to be the consequence of a combination of decreased cell number and impaired distension of the artery, possibly due to a higher stiffness associated with collagen deposition. The narrowing of resistance arteries could play a role in the pathogenesis of hypertension in this model.

Adaptation, Physiological↗
PubMed1975

[A electromyographic study of the vestibular reflexes. A clinical experimental study on human beings (author's transl)].

It is reported about myography on testpersons with normal vestibular function as well as on patients after operativ dissection of the VIII. nerve, neuropathia nerv. vest. and M. Menière. On the base of these findings it is supposed that myography proofes to be a useful help in the judgement of the specific influence of the vestibular organs on the motoric system. The myographic changes of the muscular activity after caloric stimulation give exact information about the entire vestibular system and especially about the vestibular-spinal-pathways. The best way of testing the vestibular activity is performed on musculars with symmetric, simultaneous and reziproke intented innervation, f.i. on the sternocleidomastoidei muscels in slight deflected position of the head. Most significant for the vestibular influence are an increase of the base-activity and the appearance of groups of potentials which are related to the vestibular stimulus in time and intensity.

Electromyography↗
PubMed2004

Influence of neonatal sympathectomy on proximal renal resistance artery function in spontaneously hypertensive rats.

Renal transplantation experiments have shown that the kidney contributes to chronic sympathectomy-induced arterial pressure reduction in spontaneously hypertensive rats (SHR). The underlying mechanisms are currently unclear but may include alterations in the function of small renal arteries. Neonatal SHR were sympathectomized by intraperitoneal guanethidine injections and removal of adrenal medullary tissue. Controls were sham- or hydralazine-treated. At 12 weeks of age, distal interlobar artery segments were investigated using small-vessel wire myography. Vessels from sympathectomized animals showed increased sensitivity to noradrenaline (NE). Vasopressin- and endothelin-1-induced vasoconstriction was similar in all groups (as reflected by the pD(2), i.e. -logEC(50), where EC(50) is the molar concentration of agonist eliciting a half-maximal response). Maximum vasopressin-induced tension was similar in all groups while endothelin-1-induced maximum tension was significantly higher in sympathectomized than in sham-treated SHR. The sensitivity of NE-induced vasoconstriction to extracellular Ca(2+) did not differ between groups while sensitivity to L-type Ca(2+) channel activation was significantly higher in both sympathectomized and hydralazine-treated animals than in sham-treated animals. Endothelium-dependent and independent vasodilation were similar in all groups. Sequential blockade of NO-synthase and cyclooxygenase had similar effects in all groups. In conclusion, neonatal sympathectomy does not induce any changes in the function of isolated proximal renal resistance arteries from SHR that could explain the blood pressure lowering effect of a kidney graft from sympathectomized SHR.

Animals↗
PubMed1991

Acoustic myographic activity increases linearly up to maximal voluntary isometric force in the human quadriceps muscle.

Sounds produced during voluntary isometric contractions of the quadriceps muscle were recorded by acoustic myography (AMG) in seven healthy adults. With the subject seated, surface AMG and electromyography (EMG) were recorded over rectus femoris (RF) during isometric contractions, at different levels of maximum voluntary force. The AMG and EMG signals were amplified and integrated (IAMG and IEMG). The relationships between force and IAMG (r = 0.98 +/- 0.01, mean +/- 1 SD) and force and IEMG (r = 0.99 +/- 0) were linear in all subjects. The results for EMG confirm previous reports but those for AMG differ from the relationships reported for other muscles. Physiological and technical explanations are proposed for these differences and the necessity for further validation of the AMG technique is stressed.

Acoustics↗
PubMed2004

Long-term effects of repeated pregnancies (multiparity) on blood pressure regulation.

OBJECTIVE: Pregnancy is associated with profound alterations in the cardiovascular system, the long-term effects of which are unknown. Human epidemiological studies suggest that multiparity (multiple pregnancies) increases the risk of cardiovascular disease. The mechanisms underlying these findings remain to be elucidated. The objective of this study was to determine the long-term effects of parity on cardiovascular regulation. METHODS: Pressor responses to phenylephrine (PE) and acute stress were compared in conscious age-matched repeatedly breed (RB) and virgin rats. Vascular compliance and reactivity of isolated resistance-sized mesenteric arteries were studies using pressure and wire myograph. RESULTS: We found that both exogenous PE and acute stress elicited greater pressor responses in RB than in aged-matched virgins. Pressure and wire myography also revealed that small mesenteric arteries from RB rats were less compliant than those from virgins (RB: 0.24+/-0.04 microm mm Hg(-1), n=6 vs. virgins: 0.63+/-0.06 microm mm Hg(-1), n=6; p< or =0.05) and were more sensitive to PE (EC(50) RB: 1.58+/-0.08 x 10(-6) M, n=10 vs. virgins: 2.05+/-0.09 x 10(-6) M, n=14; p< or =0.05). Removal of the endothelium abolished the difference in sensitivity. More specifically, the augmented vascular response of RB was both nitric oxide (NO) and cyclooxygenase dependent. By contrast, there was no difference in methacholine-induced vasodilation of phenylephrine-preconstricted vessels. CONCLUSION: Our results suggest that repeated pregnancies induce long-term alterations in cardiovascular regulation due to changes in vascular compliance and endothelium-dependent vasoconstriction. We propose that such changes might influence the risk for cardiovascular disease in multiparous women.

Action Potentials↗
PubMed2006

Phosphodiesterase-5 inhibitors and omental and placental small artery function in normal pregnancy and pre-eclampsia.

OBJECTIVES: In pre-eclampsia (PE), endothelium-dependent function of myometrial small arteries is markedly attenuated. The residual PE response is wholly NO mediated. We have previously demonstrated that PDE5 inhibition can improve endothelial function in myometrial small arteries from women with PE. We aimed to assess whether the effect of PDE5 inhibition in PE was myometrial artery specific. STUDY DESIGN: Small arteries were dissected from omental biopsies obtained at Caesarean section from normal pregnant women (NP, N = 20) and women with PE (N = 11). Chorionic plate small arteries were dissected from NP (N = 13) and PE (N = 11) placentae. Vasoconstriction (arginine vasopressin or thromboxane-mimetic U46619) and endothelial-dependent relaxation were assessed by wire and pressure myography. Constriction/relaxation curves were repeated post 1h incubation with PDE5 inhibitors UK-343664 or sildenafil citrate (0, 10 or 100 nM). RESULTS: Omental artery constriction was increased in PE. Omental vessel constriction was unaffected by PDE5 inhibition. Sildenafil citrate improved bradykinin-induced but not acetylcholine-induced relaxation of omental small arteries from NP women. PDE5 inhibition did not alter relaxation of omental arteries from women with PE. Placental small arteries were unaffected by PDE5 inhibition. CONCLUSION: Use of PDE5 inhibitors does not significantly alter endothelial-dependent relaxation in omental or placental small arteries from PE women.

Analysis of Variance↗
PubMed2005

The effect of maternal characteristics on endothelial-dependent relaxation of myometrial arteries.

OBJECTIVE: Endothelial dysfunction is central to the pathogenesis of pre-eclampsia (PE). This study aimed to determine if maternal characteristics, such as age, parity, BMI, smoking status and obstetric history, which affect the risk of developing pre-eclampsia, influenced endothelial function in myometrial arteries taken during an uncomplicated pregnancy. STUDY DESIGN: As part of ongoing studies investigating endothelial function in normal and compromised pregnancies, myometrial vessels were isolated from biopsies taken at elective Caesarean section. A cohort of 119 women was identified and information regarding past pregnancy outcomes and medical history was obtained. Wire myography was used to compare endothelial-dependent relaxation in response to bradykinin between different patient groups. RESULTS: Maternal age, parity and a history of miscarriage did not affect endothelial-dependent relaxation of myometrial small arteries. Attenuated endothelial-dependent relaxation was seen in vessels taken from women with elevated BMI and enhanced relaxation was seen in women who had smoked during pregnancy. Vessels isolated from women with a history of past pregnancy complications did not show any significant difference in endothelial-dependent relaxation compared to women with uncomplicated histories. CONCLUSION: Maternal factors may influence endothelial function in the absence of pregnancy complications. Endothelial-dependent relaxation of myometrial arteries, isolated from multiparous women with an uncomplicated index pregnancy, is comparable between women with and without a history of pregnancy complications.

Adult↗
PubMed1999

Measurements of vascular remodeling by confocal microscopy.

The introduction of myographs was crucial for the study of structure and function of resistance arteries. The ability to support and maintain small blood vessels paved the way for true microscopic studies of the vascular cells. However, even after decades of study, we still do not know very much about the "normal" arrangement of smooth muscle cells in the vascular wall and how their distribution affects function. It was clearly time for the next technological step forward. We have shown here how the combination of myography and confocal microscopy creates a platform for the study of vascular structure at the cellular level and in 3D. In addition, the possibility of using live myograph-mounted vessels in combination with LSCM opens a new field of research to assess vascular remodeling from a physiological point of view and to study vascular function at a level not achieved by any other method at present. Now that the hardware is in place it is time to concentrate on the software and improve the methods of analysis. We have used 2D analysis of 3D data sets to describe differences in vascular structure and, at the same time, developed methods to semiautomate the process. The success of the 3D methods will ultimately depend on the reliability and accuracy of the analysis routines. There are still problems to overcome en route to finding a complete solution. However, we believe that the search for a robust fully (or semi-) automated method of 3D analysis will be more than worthwhile. We have defined vascular remodeling to include any changes in cellular arrangement or morphology. However, on a more subtle level, changes in receptors, enzymes, and proteins leading to altered functionality could also be regarded as remodeling. In that respect it may be interesting to map the distribution of the many receptors, channels, and proteins that regulate vascular growth, death, and function. Currently, there is a growing list of fluorescent ligands and antibodies that can be used in conjunction with confocal microscopy. It is possible that multiple stains could be used and imaged at different wavelengths with a view to constructing full 3D models of various structures and their colocalization. It is our belief that the confocal approach will prove to be a major tool in unraveling the complexities of cell-cell interactions and arrangements and will allow a better understanding of the process of vascular remodeling and function.

Animals↗
PubMed2003

Vasoactive responses of veins isolated from the human placental chorionic plate.

The control of the blood flow within the fetoplacental circulation is poorly understood despite the essential role of the placenta in pregnancy. Our aim was to assess the vasoactive responses of veins from the placental chorionic plate. Biopsies were obtained from term placentae from uncomplicated pregnancies. Small veins from the chorionic plate were dissected free from surrounding tissue and studied using parallel wire myography. Human placental chorionic plate veins developed maintained constrictions to the thromboxane-mimetic U46619. Endothelium-dependent agonists did not promote venous relaxation. However, NO donation with the endothelial-independent agent, sodium nitroprusside, elicited significant relaxation. Venous constriction to U46619 and relaxation to sodium nitroprusside were modified by adjustment of media oxygen tension and normalization parameters. Human placental chorionic plate veins respond to vasoactive agents and may play a role in the control of the blood flow in the fetoplacental circulation.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2002

Preserved contractility without side bias in endovascular filament models for subarachnoid hemorrhage.

It is currently unknown whether endovascular filament (EF) models of acute subarachnoid hemorrhage (SAH) introduce any 'side bias' upon cerebrovascular reactivity by virtue of unilateral carotid manipulation, unilateral EF insertion, or potentially ipsilateral site of intracranial rupture. In this study, three experimental groups of adult male wistar rats were used: non-operated controls (n=20), sham operated controls (n=8), and SAH groups (n=26). All were anaesthetized with intraperitoneal 25% urethane (1 g/kg) except n=2 anaesthetized with intraperitoneal hypnorm/hypnovel. SAH was created by advancing an intraluminal thread through the intracranial internal carotid artery from an extracranial source in the neck. Using in vitro wire myography in all three groups, middle cerebral artery (MCA) responses ipsilateral and contralateral to EF insertion were compared using a range of vasoconstrictors and vasodilators within 3 h of SAH. No significant side differences in MCA reactivity were found with any agent in any group or sub-group analysed. In conclusion, EF-SAH models do not appear to introduce any significant 'side bias' upon ipsilateral MCA reactivity by virtue of the potentially confounding combination: (1) unilateral carotid manipulation, (2) unilateral EF insertion or (3) potentially ipsilateral intracranial rupture. They may thus be more confidentally used for post-SAH ex vivo cerebral vessel study--acute or delayed.

Acute Disease↗
PubMedDate not supplied

The age-dependent vasodilatation and endothelial calcium influx induced by elastin peptides are modulated by extracellular glucose level.

Elastin peptides have been shown to produce many biological effects on various cell types, including an endothelium- and NO-dependent vasodilatation mediated by extracellular calcium influx and intracellular calcium elevation. Under normal concentration of extracellular glucose, the vasodilatory effect is observed in adult rats and is lost with age. Here, we have studied the consequences of extracellular glucose level changes on these effects triggered by elastin peptides (10(-4)-10(-3) mg ml(-1)), on 6- and 30-month-old rats, using the tension myography and the patch-clamp techniques. Our results show that low (0 mM) or high (33 mM) extracellular glucose concentrations abolish the extracellular calcium influx induced, under normal glucose level (11 mM), by the elastin peptides in cultured human endothelial cells. Also, low or high glucose abolish the vasodilatory action of elastin peptides observed on aorta rings from adult rats under normal glucose concentration. On the contrary, a dilation of aged rat aorta is observed in the presence of elastin peptides and high glucose, whereas such dilation is not observed when the elastin peptides are added in the presence of normal glucose concentration. In aging, a restoration by high glucose of the NO-dependent vasodilatation induced by elastin peptides could enhance the production of damaging peroxynitrite, potentially altering the structure and function of the blood vessels. These results could be of importance in the evaluation and treatment of aged patients with pathophysiological dysregulations of the circulating glucose level, such as in diabetes, age-related glucose intolerance, or low glucose levels caused by inappropriate glucose control treatments.

Aging↗
PubMedDate not supplied

Relationship of cell adhesion molecule expression to endothelium-dependent relaxation in normal pregnancy and pregnancies complicated with preeclampsia or fetal growth restriction.

OBJECTIVES: To determine the degree of endothelium-dependent relaxation in myometrial and omental resistance arteries from normal pregnancies and pregnancies complicated with preeclampsia or fetal growth restriction (FGR) (compromised pregnancy group), and to correlate the results with the endothelial surface expression of cell adhesion molecules (CAMs) in the same vessels. METHODS: Parallel wire myography was used to assess the relaxation of omentum or myometrial vessels obtained from nonpregnant women (n = 3), women with normal pregnancies (n = 11), and women with pregnancies complicated by preeclampsia or fetal growth restriction (n = 10). These resistance vessels were constricted with incremental concentrations of vasopressin (10(-10) mol/L to 3.3 x 10(-8) mol/L) prior to the addition of incremental concentrations of bradykinin (10(-10) mol/L to 3.3 x 10(-6) mol/L). Immunohistochemistry was used to assess the endothelial expression of the CAMs E-selectin, ICAM-1, VCAM-1, and PECAM. RESULTS: A significant reduction in endothelium-dependent relaxation of myometrial vessels was found in the compromised pregnancy group when compared with both the normotensive pregnant group and the nonpregnant group. This reduction was not noted with omental vessels. All vessels in the nonpregnant group, normal pregnant group, and compromised pregnancy group expressed PECAM and ICAM-1 on the endothelium. There was no difference in intensity of immunostaining between the groups. None of the vessels in any of the groups expressed VCAM-1 or E-selectin. CONCLUSIONS: We found no evidence that impaired relaxation responses to bradykinin are linked to altered expression of CAMs in preeclampsia and FGR. These results suggest that increased CAM expression occurs in a vascular bed separate from those investigated in the present study. Possible sites for this would be in the microcirculation of organs such as the kidney.

Adult↗
PubMed2004

Non-esterified fatty acids impair endothelium-dependent vasodilation in rat mesenteric resistance vessels.

Elevated circulating levels of NEFAs (non-esterified fatty acids) are associated with states of insulin resistance and increased risk of vascular disease. Previous animal and human studies have demonstrated NEFA-induced endothelial dysfunction of large conduit arteries, reversible by the antioxidant ascorbic acid. We therefore investigated the effect of NEFAs on carbachol-induced endothelium-dependent vasodilation of rat resistance arteries in vitro using the technique of wire myography. In addition, we investigated the effect of co-incubation of NEFAs and ascorbic acid. Cumulative concentration-response curves to carbachol (endothelium-dependent vasodilation) and SNAP (S-nitroso-N-acetyl-DL-penicillamine; endothelium-independent vasodilation) were constructed. Those to carbachol were repeated following a 30 min incubation with either oleic acid (10(-4) M) or palmitic acid (10(-4) M), demonstrating significant impairment of endothelium-dependent vasodilation with both [P<0.05, comparison of pD2 values (the negative log concentration of agonist required to effect a 50% response)]. A cumulative concentration-response curve to carbachol was repeated following co-incubation with palmitic acid (10(-4) M) and the antioxidant ascorbic acid (10(-5) M), demonstrating an abolition of the previously observed endothelial dysfunction induced by palmitic acid. There was no impairment of vasodilation to SNAP following NEFA incubation. We conclude that NEFAs directly impair endothelial function in rat resistance arteries via an increase in oxidative stress at the vascular endothelium.

Animals↗