Abstract
The contributions of individual components of blood to brain [14C]palmitate uptake and incorporation were studied with the in situ brain perfusion technique in the pentobarbital-anesthetized rat. With whole-blood perfusate, brain unacylated [14C]palmitate uptake was linear with time and extrapolated to zero at T=0 s of perfusion. Tracer accumulated in brain with a blood-to-brain transfer coefficient of 1.8 ± 0.1 × 10−4 mL/s/g (whole cerebral hemisphere). Incorporation into brain lipids was rapid such that ∼40% of tracer in brain at 45 s of perfusion was in cerebral phospholipids and neutral lipids. Similar rates of uptake were obtained during unacylated [14C]palmitate perfusion in whole rat plasma, serum, or artificial saline containing 2–3% albumin, suggesting that albumin has a key role in determining [14C]palmitate uptake in brain. The excellent match in brain uptake rates between whole blood and albumin-containing saline fluid suggests that the perfusion technique will be useful method for quantifying the individual contributions of blood constituents and albumin binding on brain [14C]palmitate uptake.
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Smith, Q.R., Nagura, H. Fatty acid uptake and incorporation in brain. J Mol Neurosci 16, 167–172 (2001). https://doi.org/10.1385/JMN:16:2-3:167
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DOI: https://doi.org/10.1385/JMN:16:2-3:167