Biopterin : I. Profile and quantitation in rat brain.

摘要: Intraperitoneally injected [(14)C]biopterin (B), dihydrobiopterin (BH2), and tetrahydrobiopterin (BH4) penetrated the brain rapidly, but in amounts sufficient to represent only a minor source of supply. Unlike isobiopterin, B was rapidly reduced BH2 brain. The distribution BH4 BH2, not B, could be correlated with tryptophan tyrosine hydroxylase activity various cerebral areas. In whole brain, sizes pools were 0.117 for 0.204 0.341 μg/g BH4, while turnover rates 0.25, 0.43, 0.71 nmol/g per h, respectively. From birth through development, levels remained constant, whereas biopterins increased. After subcellular fractionation, 65% (B, BH4) recovered from supernatant. Of organelles, microsomes contained largest concentration pterins. About 1/6 all pterins present synaptosomes.