METHODS: Chorionic arteries and veins were isolated from human placenta from normal, gestational diabetes mellitus and type 1 diabetes mellitus pregnancies. Isometric tension recording measured responses to adenosine and the thromboxane A2 analogue U46619 (thromboxane A2 mediates fetoplacental vasoconstriction to adenosine). Adenosine and thromboxane prostanoid receptor protein expression was determined by immunoblotting.
RESULTS: Adenosine elicited contractions in chorionic arteries and veins which were impaired in both gestational diabetes mellitus and type 1 diabetes mellitus. Contractions to potassium chloride were unchanged. Adenosine A2A and A2B receptor protein levels were not different in gestational diabetes mellitus and normal pregnancies. Contractions to U46619 were unaltered in gestational diabetes mellitus arteries and increased in type 1 diabetes mellitus arteries. Overnight storage of vessels restored contractility to adenosine in gestational diabetes mellitus arteries and normalized contraction to U46619 in type 1 diabetes mellitus arteries.
CONCLUSION: These data are consistent with the concept of aberrant adenosine signalling in diabetes; they show for the first time that this involves impaired adenosine contractility of the fetoplacental vasculature.
METHODS: Patients enrolled in the PROGRESS registry were evaluated for use of vasopressor and LDC (equivalent or lesser potency to hydrocortisone 50 mg six-hourly plus 50 microg 9-alpha-fludrocortisone) for treatment of severe sepsis at any time in intensive care units (ICUs). Baseline characteristics and hospital mortality were analyzed, and logistic regression techniques used to develop propensity score and outcome models adjusted for baseline imbalances between groups.
RESULTS: A total of 8,968 patients with severe sepsis and sufficient data for analysis were studied. A total of 79.8% (7,160/8,968) of patients received vasopressors, and 34.0% (3,051/8,968) of patients received LDC. Regional use of LDC was highest in Europe (51.1%) and lowest in Asia (21.6%). Country use was highest in Brazil (62.9%) and lowest in Malaysia (9.0%). A total of 14.2% of patients on LDC were not receiving any vasopressor therapy. LDC patients were older, had more co-morbidities and higher disease severity scores. Patients receiving LDC spent longer in ICU than patients who did not (median of 12 versus 8 days; P <0.001). Overall hospital mortality rates were greater in the LDC than in the non-LDC group (58.0% versus 43.0%; P <0.001). After adjusting for baseline imbalances, in all mortality models (with vasopressor use), a consistent association remained between LDC and hospital mortality (odds ratios varying from 1.30 to 1.47).
CONCLUSIONS: Widespread use of LDC for the treatment of severe sepsis with significant regional and country variation exists. In this study, 14.2% of patients received LDC despite the absence of evidence of shock. Hospital mortality was higher in the LDC group and remained higher after adjustment for key determinates of mortality.
METHODS: Twelve Sprague-Dawley rats received either 20% fructose solution [FFR] or tap water [C] to drink ad libitum for 8 weeks. The renal vasoconstrictor response to noradrenaline (NA), phenylephrine (PE), methoxamine (ME) and Ang II was determined in the presence and absence of 5-methylurapidil (5-MU) (α1A-adrenoceptor antagonist) in a three-phase experiment (pre-drug, low- and high-dose 5-MU). Data, mean ± SEM were analysed by ANOVA or Student's unpaired t-test with significance at P < 0.05.
RESULTS: FFR exhibited insulin resistance (HOMA index), hypertension and significant increases in plasma levels of glucose and insulin. All agonists caused dose-related reductions in cortical blood perfusion that were larger in C than in FFR while the magnitudes of the responses were progressively reduced with increasing doses of 5-MU in both C and FFR. The degree of 5-MU attenuation of the renal cortical vasoconstriction due to NA, ME and Ang II was significantly greater in the FFR compared to C.
CONCLUSIONS: Fructose intake for 8 weeks results in smaller vascular response to adrenergic agonists and Ang II. The α1A-adrenoceptor subtype is the functional subtype that mediates renal cortical vasoconstriction in control rats, and this contribution becomes higher due to fructose feeding.