Aluminum 이 백서의 뇌중 Choline uptake 및 Choline Acetyltransferase와 Acetylcholinesterase의 활성도에 미치는 효과에 관한 연구

Effects of Aluminum on Choline uptake and Activities of Choline Acetyltransferase and Acetylcholinesterase in Rat Brain

The uptake of C3H ) choline into synaptosomes prepared from rat corpus striatum and frontal cortex was studied at choline concentration varying from 0.05 to 2.0 |iM. The sodiumdependent high affinity choline uptake in these brain regions exhibited saturation kinetics with Km values o f 0.37 (iM in corpus striatum and 0.35(iM in frontal cortex. A l3+ inhibited total choline uptake at concentrations greater than 10-4 M. Double-reciprocal plots indicated that A l3+ was a noncompetitive inhibitor o f high affinity choline uptake with Ki values of 2.17X10 3 M in corpus striatum and 0.82 X10 3 M in frontal cortex. The presence of 1 m M Ca2+ neither influenced high affinity choline uptake, nor antagonized the inhibitory effects of A l3+. A l3+ did not alter the activities of choline acetyltransferase and acetylcholinesterase at all substrate and inhibitor concentrations studied. These data suggest that high A l3+ levels modify cholinergic transmission by inhibition of high affinity choline uptake