Aging and diabetes in women increase their susceptibility to myocardial ischemic injury, but the cellular mechanisms involved are not understood. Consequently, we studied the influence of gender on cardiac insulin resistance and ischemic injury in the aging of Goto-Kakizaki (GK) rat, a model of type 2 diabetes. Male and female GK rats had heart/body weight ratios 29% (P < 0.
View Article and Find Full Text PDFObjective: Whole body insulin resistance and diabetes are risk factors for cardiovascular diseases, yet little is known about insulin resistance in the diabetic heart. The aim of this work was to define the insulin response in hearts of the Goto-Kakizaki (GK) rat, a polygenic model of spontaneous type 2 diabetes.
Methods: We measured D[2-3H]glucose uptake before and after insulin stimulation, plus initial steps of the insulin signaling pathway after insulin infusion via the caudal vena cava in hearts from the male Wistar and spontaneously diabetic GK rats.
Obesity is associated with risk factors for cardiovascular disease, including insulin resistance, and can lead to cardiac hypertrophy and congestive heart failure. Here, we used the insulin-sensitizing agent rosiglitazone to investigate the cellular mechanisms linking insulin resistance in the obese Zucker rat heart with increased susceptibility to ischemic injury. Rats were treated for 7 or 14 days with 3 mg/kg per os rosiglitazone.
View Article and Find Full Text PDFBurkitt's lymphoma cell lines have been important in vitro models for studying the pathogenesis of Burkitt's lymphoma (BL) and for exploring new treatment strategies. A new EBV(-) Burkitt's lymphoma cell line (GA-10) was established from a patient with a clinically aggressive, chemorefractory BL and characterized. Although functional p-glycoprotein could not be demonstrated by dye-efflux assays, both p53 genes were mutated in the GA-10 cells, perhaps contributing to the resistant phenotype of the original neoplasm.
View Article and Find Full Text PDFAm J Physiol Heart Circ Physiol
March 2001
To determine whether the effects of fatty acids on the diabetic heart during ischemia involve altered glycolytic ATP and proton production, we measured energetics and intracellular pH (pH(i)) by using (31)P NMR spectroscopy plus [2-(3)H]glucose uptake in isolated rat hearts. Hearts from 7-wk streptozotocin diabetic and control rats, perfused with buffer containing 11 mM glucose, with or without 1.2 mM palmitate or the ketone bodies, 4 mM beta-hydroxybutyrate plus 1 mM acetoacetate, were subjected to 32 min of low-flow (0.
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