TY - JOUR
T1 - [3H]Methotrexate Loss from the Rat Brain following Enhanced Uptake by Osmotic Opening of the Blood-Brain Barrier
AU - Ohata, Masahiro
AU - Fredericks, Wendy R.
AU - Neuwelt, Edward A.
AU - Sundaram, Uma
AU - Rapoport, Stanley I.
PY - 1985/3/1
Y1 - 1985/3/1
N2 - Right brain regions of anesthetized rats were loaded with [3,5,7-3H]methotrexate (3H]MTX) or with [14C]sucrose by infusing the tracers into the right carotid artery, after the blood-brain barrier had been opened by right carotid infusion of a hypertonic arabinose solution. During the 6 hr following the procedure, the [3H]MTX concentration in 7 right-sided brain regions, when normalized to the plasma concentration integral during tracer infusion, fell, with an average half-time of 4.8 hr as compared to less than 20 min for the initial rate of toss of [14C]sucrose. Right-left brain concentration differences 3 hr after treatment were statistically significant (p < 0.05) for [3H]MTX but not for [14C]sucrose. The results indicate that intracerebral [3H]MTX is lost more slowly than is intracerebral [14C]sucrose, possibly because [3H]MTX enters brain cells, whereas [14C]sucrose remains largely extracellular.
AB - Right brain regions of anesthetized rats were loaded with [3,5,7-3H]methotrexate (3H]MTX) or with [14C]sucrose by infusing the tracers into the right carotid artery, after the blood-brain barrier had been opened by right carotid infusion of a hypertonic arabinose solution. During the 6 hr following the procedure, the [3H]MTX concentration in 7 right-sided brain regions, when normalized to the plasma concentration integral during tracer infusion, fell, with an average half-time of 4.8 hr as compared to less than 20 min for the initial rate of toss of [14C]sucrose. Right-left brain concentration differences 3 hr after treatment were statistically significant (p < 0.05) for [3H]MTX but not for [14C]sucrose. The results indicate that intracerebral [3H]MTX is lost more slowly than is intracerebral [14C]sucrose, possibly because [3H]MTX enters brain cells, whereas [14C]sucrose remains largely extracellular.
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M3 - Article
C2 - 3971363
AN - SCOPUS:0021894552
SN - 0008-5472
VL - 45
SP - 1092
EP - 1096
JO - Cancer Research
JF - Cancer Research
IS - 3
ER -