The 10-year incidence of hypertension across blood pressure categories in a population-based cohort in southwestern Sweden.

BACKGROUND: To explore the determinants of incident hypertension, and especially the impact of baseline blood pressure categories, in a representative Swedish population. METHODS: A 10-year longitudinal study of residents aged 30-74. Blood pressures were measured and categorized according to ESH guidelines with optimal blood pressure < 120/80 mmHg, normal 120-129/80-84 mmHg, and high normal 130-139/85-89 mmHg. Incident hypertension was defined as ongoing treatment or three consecutive blood pressure readings ≥ 140/ ≥ 90 mmHg (one or both) at follow-up, while those with ≥ 140 and/or ≥ 90 mmHg at only one or two visits were labelled as unstable. After excluding subjects with hypertension, ongoing blood pressure lowering medication or a previous CVD event at baseline, 1099 remained for further analyses. RESULTS: Sixteen (2.6%) subjects with optimal baseline blood pressure had hypertension at follow up. Corresponding numbers for subjects with normal, high normal and unstable blood pressure were 55 (19.4%), 50 (39.1%) and 46 (74.2%), respectively. Compared with subjects in optimal group those in normal, high normal and unstable blood pressure categories had significantly higher risk to develop manifest hypertension with odds ratios OR and (95% CI) of 7.04 (3.89-12.7), 17.1 (8.88-33.0) and 84.2 (37.4-190), respectively, with adjustment for age, BMI and family history for hypertension. The progression to hypertension was also independently predicted by BMI (p < 0.001), however, not by age. CONCLUSIONS: Subjects with high normal or unstable blood pressure should be identified in clinical practice, evaluated for global hypertension risk and offered personalized advice on lifestyle modification for early prevention of manifest hypertension and cardiovascular disease.

Study of the beta1 adrenergic receptor expression in human tissues: immunological approach.

Questions exist regarding tissue distribution of the beta1 adrenergic receptor (beta1-AR). The aim of this study was to investigate relative distribution patterns of the beta1-AR at the protein level in a variety of human tissues by Western blot analysis. The specificity of anti-peptide antibodies was confirmed both by Western blot with recombinant beta1-AR expressed as a membrane protein in E. coli and by immunoprecipitation of membranes from Sf9 cells infected with baculovirus to express the human recombinant beta1-AR. beta1-AR was found in all tissues examined. The relative amount of protein varied significantly between the tissues, from highest in lung and testis to very low in liver. beta1-ARs were rather abundant in heart, kidney, placenta, spleen and thyroid. These results reveal unique distribution of beta1-AR protein that suggests its tissue specific role. Moreover, our data demonstrate a high sensitivity of immunological detection that allows direct comparison of beta1-AR subtype expression and could be used for receptor study in biopsies available in limited amounts, such as human heart biopsy.

Muscarinic M3 receptor subtype gene expression in the human heart.

The heart is an important target organ for cholinergic function. In this study, muscarinic receptor subtype(s) in the human heart were determined using reverse transcription-polymerase chain reaction. Our results demonstrated muscarinic receptor M2 and M3 subtype RNA in left/right atria/ventricles of donor hearts. Receptor autoradiography analysis using selective muscarinic ligands indicated an absence of M1 receptor subtype in the human heart. The level of muscarinic receptor binding in atria was two to three times greater than in ventricles. Our results suggest that muscarinic receptors in the human heart are of the M2 and M3 subtypes. This is the first report of M3 receptors in the human myocardium.

Combination of angiopoietin-1 and vascular endothelial growth factor gene therapy enhances arteriogenesis in the ischemic myocardium.

We hypothesised that angiopoietin-1 (Ang-1), in conjunction with vascular endothelial growth factor (VEGF) gene therapy, can enhance arteriogenesis and angiogenesis during myocardial ischemia. Mice were given a single intramyocardial injection of saline, phVEGF-A(165) and phAng-1 or a combination thereof into the non-ischemic normal heart or into the ischemic border zone of the infarcted heart. In the normal and the ischemic myocardium, gene transfer of phVEGF-A(165) alone increased the myocardial capillary density by 16% and 36%, respectively, and phAng-1 had a similar effect. In the normal heart, the ratio of arteriolar to capillary densities increased with phVEGF-A(165) and more so in the ischemic myocardium where phAng-1 also had an effect. Furthermore, the combination of plasmids induced an up to 7.5-fold increase. Transient overexpression of VEGF-A(165) boosts endogenous arteriogenesis in addition to capillary angiogenesis. Ang-1 further boosts this effect at the arteriolar level.

Highly efficient cell-mediated gene transfer using non-viral vectors and FuGene6: in vitro and in vivo studies.

The present study was undertaken to develop an efficient non-viral gene delivery system for cardiovascular gene therapy. We investigated transfection efficiency and toxic properties of the new transfection reagent, FuGene6, and compared it with two other transfection reagents, Tfx-50 and LipoTaxi. For in vivo experiments, the plasmid was delivered intramuscularly via transplantation of fibroblasts transfected with plasmid and FuGene6. Conditions for efficient gene delivery were initially studied in vitro. Human and rabbit fibroblasts were isolated from skin, cultured and transfected with phVEGF165 or pCMVbeta gal plasmids, coding for vascular endothelial growth factor (VEGF) or beta-galactosidase, respectively. The effect of the DNA amount and the DNA:transfection reagent ratio on plasmid uptake were studied. Of the transfection reagents tested, only FuGene6 provided high-efficiency and dose-dependent plasmid transfer both for cell-localised (beta-galactosidase) and secreted (VEGF) gene products. When analysed with an MTT assay, FuGene6 showed no toxicity at low doses. Optimised conditions were applied for in vivo reporter gene delivery. Rabbits were injected intramuscularly with ex vivo-transfected fibroblasts. As in in vitro studies, ex vivo-transfected fibroblasts showed highly efficient gene expression in vivo. Tissue sections were analysed with macrophage-specific immunostaining. No signs of inflammation were seen in the region of fibroblast injection. This study demonstrates that FuGene6 is a highly efficient transfection reagent that may be useful for in vitro non-viral transfection of primary human and rabbit fibroblasts and for in vivo therapeutic non-viral gene delivery.