Then rats were tested on the 5-CSRTT under baseline task parameters, under increased task difficulty (behavior challenge condition), and finally in muscarinic and nicotinic drug challenge conditions. In a second experiment,
10-month-old rats were trained on the 5-CSRTT and at 12 or 17 months of age rats were ovariectomized and treated with estradiol or cholesterol, so that one group received continuous cholesterol control treatment, two groups received estradiol treatment immediately following ovariectomy (either at 12 or 17 months), and one group received delayed estradiol treatment initiated 5 months following ovariectomies. At 17 months of age, rats Pictilisib solubility dmso were tested on the 5-CSRTT. Baseline performance was comparable between estradiol- and cholesterol-treated rats of both age groups. However, young estradiol-treated rats outperformed controls when behavior was challenged by shortening the intertrial interval (Short III). In the same Short ITI condition, middle-aged rats receiving immediate 10058-F4 estradiol treatment beginning at the age of 17 months, but not 12 months, outperformed controls as well as animals receiving delayed estradiol treatment. No differences between groups were found
in the cholinergic drug challenge conditions. These data indicate that chronic estradiol treatment for approximately 1 month but not 6 months is able to enhance attention performance, and that prolonged ovarian hormone deprivation attenuates these beneficial effects of subsequent estradiol treatment. These findings have implications for informing clinical research about the importance of timing and duration of hormone
treatment. (c) 2009 Elsevier Ltd. All rights reserved.”
“Introduction: Dietary conditions may affect liver [F-18]FDG kinetics due to arterial and portal vein (PV) PF-6463922 clinical trial input. The purpose of this study was to evaluate kinetic models of [F-18]FDG metabolism under a wide range of dietary interventions taking into account variations in arterial (HA) and portal vein (PV) input.
Methods: The study consisted of three groups of rats maintained under different diet interventions: 12 h fasted, 24 h fasted and those fed with high fructose diet. [O-15]H2O PET imaging was used to characterize liver flow contribution from HA and PV to the liver’s dual input function (DIF). [F-18]FDG PET imaging was used to characterize liver metabolism. Differences in [F-18]FDG kinetics in HA, PV and liver under different diet interventions were investigated. An arterial to PV Transfer Function (TF) was optimized in all three dietary states to noninvasively estimate PV activity. Finally, two compartment 3-parameter (2C3P), two compartment 4-parameter (2C4P), two compartment 5-parameter (2C5P), and three compartment 5-parameter (3C5P) models were evaluated and compared to describe the kinetics of [F-18]FDG in the liver across diet interventions.