| 1. |
- Dimitrijevic, Ivan, et al.
(författare)
-
Increased expression of endothelin ETB and angiotensin AT(1) receptors in peripheral resistance arteries of patients with suspected acute coronary syndrome
- 2009
-
Ingår i: Heart and Vessels. - : Springer Science and Business Media LLC. - 1615-2573 .- 0910-8327. ; 24:6, s. 393-398
-
Tidskriftsartikel (refereegranskat)abstract
- Patients who experience chest pain, in which ischemic heart disease has been ruled out, still have an increased risk of future ischemic cardiac events and premature death, possibly due to subclinical endothelial dysfunction. A feature of endothelial dysfunction is an increased expression of arterial vasoconstrictor endothelin (ET) and angiotensin (AT) receptors. Our aim was to investigate if the arterial expressions of these receptors are changed in patients with suspected but ruled out acute coronary syndrome (ACS). Small subcutaneous arteries (diameter of 100 A mu m) were surgically removed in an abdominal biopsy from 12 patients suspicious of ACS (susp ACS), admitted to the medical telemetry unit for chest pain. The vessels were analyzed for their receptor protein expression by quantitative immunohistochemistry using specific antibodies directed against ETA, ETB, AT(1), and AT(2) receptors. The control group (controls) consisted of eight healthy volunteers matched for age and sex with no previous cardiac illness or medication. The susp ACS group had an increased expression of ETB (by 94%) and AT(1) (by 34%) receptors in the smooth muscle cells of resistance arteries as compared to the control group. There were no significant differences in AT(2) and ETA receptor expression between the groups. The results indicate that the expression of arterial smooth muscle ETB and AT(1) receptors are increased in patients with suspected but ruled out ACS. These receptor changes could be important in the regulation of coronary tone and in the development of atherosclerosis, and may be related to increased cardiovascular risk.
|
|
| 2. |
- Edvinsson, MarieLouise, et al.
(författare)
-
Brain natriuretic peptide is a potent vasodilator in aged human microcirculation and shows a blunted response in heart failure patients.
- 2014
-
Ingår i: Journal of geriatric cardiology : JGC. - 1671-5411. ; 11:1, s. 50-56
-
Tidskriftsartikel (refereegranskat)abstract
- Brain natriuretic peptide (BNP) is normally present in low levels in the circulation, but it is elevated in parallel with the degree of congestion in heart failure subjects (CHF). BNP has natriuretic effects and is a potent vasodilator. It is suggested that BNP could be a therapeutic alternative in CHF. However, we postulated that the high levels of circulating BNP in CHF may downregulate the response of microvascular natriuretic receptors. This was tested by comparing 15 CHF patients (BNP > 3000 ng/L) with 10 matched, healthy controls.
|
|
| 3. |
- Edvinsson, MarieLouise, et al.
(författare)
-
Cigarette smoking leads to reduced relaxant responses of the cutaneous microcirculation.
- 2008
-
Ingår i: Vascular Health and Risk Management. - 1178-2048. ; 4:3, s. 699-704
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Smoking is a major risk factor for cardiovascular disease. The present study was undertaken to examine if cigarette smoking translates into reduced relaxant responses of the peripheral microcirculation. METHODS: The cutaneous forearm blood flow was measured by laser Doppler flowmetry. The vasodilator response to the iontophorectic administration of acetylcholine (ACh), acting via an endothelial mechanism, and sodium nitroprusside (SNP), and acting via a smooth muscle mechanism were studied. The study population consisted of 17 nonsmokers and 17 current smokers (mean age 64+/-2 years, 13 females and 4 males) in each matched group. RESULTS: There was no difference between the groups in baseline characteristics or in basal flow. Smokers showed however significantly reduced responses to both ACh (mean +/- SEM, from 973+/-137% in nonsmokers to 651+/-114% in smokers, p<0.05) and SNP (from 575+/-111% in nonsmokers to 355+/-83% in smokers, p<0.05). The response to the local heating (44 degrees C) was reduced in smokers (from 1188+/-215% in nonsmokers to 714+/-107% in smokers, p<0.01). In addition, there was no difference between men and women within the groups. CONCLUSIONS: The data show that cigarette smoking results in reduced peripheral microvascular responses to both endothelial and smooth muscle cell stimulation in healthy subjects, suggesting a generalized microvascular vasomotor function.
|
|
| 4. |
- Edvinsson, MarieLouise
(författare)
-
Natriuretic Peptides and the Microcirkulation in Heart Failure Patients
- 2014
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The increased prevalence of chronic congestive heart failure (HF) is a tremendous challenge for society. In spite of effective medical treatment for acute HF, better pharmacological treatment for specific neurohormonal intervention and better diagnostic tools, e.g. biomarkers of natriuretic peptides, the morbidity and mortality due to this disease are still prominent. HF leads to vascular dysfunction in the general circulation but the interpretation of this is not clear. In our studies we have focussed on defining endothelial and smooth muscle dysfunction in the microvasculature of HF patients and correlating this dysfunction with the disease state. This thesis addresses studies of elderly patients with varying degrees of HF. We determined blood levels of homocysteine and the natriuretic peptide precursor, NT-proBNP which is released by the failing heart. We also investigated vasoreactive response of the cutaneous microcirculation to different stimuli using a non-invasive iontophoresis-Laser Doppler probe method. Paper I: We investigated the prognostic value of NT-proBNP for monitoring progression of HF. High blood levels (>5000) were found to indicate a poor prognosis of HF. Paper II: An open study,- in which we evaluated the function of the cutaneous peripheral circulation of patients with chronic HF. We found that vasoreactivity declines with increasing age and HF. Paper III: We evaluated vasoreactive responses in HF patients with homocysteinemi, before and 6 weeks after supplementary by B vitamin treatment. Homocysteine levels where then normalized and the cutaneous responses improved. Paper IV: A controlled study in which, we investigated the microcirculation in chronic HF patients with different degrees of HF. We saw that the degree of severity of congestive HF did not correlate with decrease in vasoreactive responses. Paper V: The effect of BNP in the microcirculation was studied in patients with severe congestive HF and compared to healthy, matched controls. The result shows that BNP has a significantly weaker vasodilation in HF patients and this is probably due to down regulation at the receptor-coupling level.
|
|
