## Abstract In adult rats, using the single‐pass brain uptake technique with a tritiated water standard, L‐phenylalanine was shown to enter brain across the blood‐brain barrier (BBB) by both a saturable and diffusionary process. A kinetic analysis of the data revealed Michaelis constant (K~a~) of 0
Starvation-induced changes in transport of ketone bodies across the blood-brain barrier
✍ Scribed by Dr. Michael Pollay; F. Alan Stevens
- Publisher
- John Wiley and Sons
- Year
- 1980
- Tongue
- English
- Weight
- 554 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0360-4012
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The permeability of the blood brain barrier (BBB) to β‐hydroxybutyrate (β‐HB) was computed in fed and starved (five days) rats by the simultaneous measurement of cerebral blood flow (diffusible indicator method‐^123^I‐iodoantipyrine) and brain uptake of ^14^C‐β‐HB (relative to a ^3^H~2~O reference). The results from the present study demonstrate that the movement of β‐HB across the BBB in rat is by a carrier‐mediated process. During starvation, total movement (carrier‐mediated and diffusionary) of this ketone body into brain was observed to be enhanced because of an increase in the diffusionary loss across the cerebral capillary. The calculated transport kinetics also suggest that the β‐HB molecule has a greater affinity for the transport (mediator) protein during starvation, although the maximal rate of uptake by brain due to a carrier processes mediated V~max~ is decreased either because there is a smaller quantity of the mediating molecule or because there is trans inhibition by a high cellular concentration of β‐HB or some analog.
📜 SIMILAR VOLUMES
## Abstract The brain capillary endothelium is a formidable barrier to entry of foreign chemicals into the central nervous system (CNS). For the most part it poorly distinguishes between therapeutics and neurotoxins and thus the blood‐brain barrier both protects the brain from toxic chemicals and l
A brain to blood carrier-mediated transport system observation that many of the central effects observed with for arginine vasopressin (AVP) was investigated in the intraventricular administration of AVP can also be mice after intraventricular injection of iodinated AVP achieved by injection of subs
To characterize pentazocine (PTZ) transport across the blood-brain barrier (BBB), the cerebrovascular permeability-surface area product (PS(inf)) of PTZ was determined by a well-established in situ rat brain perfusion technique. The uptake kinetics of PTZ by the rat brain exhibited saturability, whi