The dose-response relation between plasma glucose and brain lactate and the relation of these parameters to intracellular pH during severe cerebral ischemia have not been well characterized over a wide range of plasma glucose levels. Experiments to delineate these relations in the gerbil model of global ischemia were performed by using phosphorus-31 nuclear magnetic resonance spectroscopy to me...

Brain serotonin cocentrations at 1 p.m. were significantly elevated 1 hour after rats received a dose of L-tryptophan (12.5 milligrams per kilogram. intraperitoneally) smaller than one-twentieth of the normal daily dietary intake. Plasma and brain tryptophan levels were elevated 10 to 60 minutes after the injection, but they never exceeded the concentrationis that occur nocturnally in untreated...

The purpose of this work was to inspect the potential of vincristine-dextran complex loaded solid lipid nanoparticles for drug delivery to the brain. The nanoparticles were stained with a fluorescence dye and their plasma pharmacokinetic and brain concentrations were investigated following injection to rats. The result revealed a significant improvement in the plasma concentration profile of th...

introduction: the brain glutamate neurotransmitter system and its nmda receptors in the nucleus accumbens play an important role in the incidence of the phenomena of sensitivity and addiction. the present study examined the inhibitory effect of glutamate nmda receptors in the nucleus accumbens in response to chronic stress. methods: after the unilateral and bilateral cannula placement in the nu...

background and aims: a selective and sensitive high performance liquid chromatography-electrospray ionization mass spectrometry method has been established for determination of methotrexate in human plasma. methods: methotrexate was extracted from plasma with acetonitrile. the mobile phase consisted of acetonitrile-water-formic acid 74: 25: 1(v/v). twenty µl of sample was chromatographically an...

The effect of gender on systemic and brain levels of copper is relatively understudied. We examined gender effects in mice and human subjects. We observed a trend to higher serum copper levels in female compared to male LaFerla "triple transgenic" (1399 ± 233 versus 804 ± 436 ng/mL, P = 0.06) mice, and significantly higher brain copper levels in female- versus male wild-type mice (5.2 ± 0.2 ver...

Bentourkia M, Tremblay S, Pifferi F, Rousseau J, Lecomte R, Cunnane S. PET study of C-acetoacetate kinetics in rat brain during dietary treatments affecting ketosis. Am J Physiol Endocrinol Metab 296: E796 –E801, 2009. First published January 27, 2009; doi:10.1152/ajpendo.90644.2008.—Normally, the brain’s fuel is glucose, but during fasting it increasingly relies on ketones ( -hydroxybutyrate, ...

We have investigated whether side chain-hydroxylated cholesterol species are important for elimination of cholesterol from the brain. Plasma concentrations of 24-hydroxycholesterol (24-OH-Chol) in the internal jugular vein and the brachial artery in healthy volunteers were consistent with a net flux of this steroid from the brain into the circulation, corresponding to elimination of approximate...