Pandey A, Habibulla M, Singh R
Brain Res. 1983 Aug 22;273(1):67-70. doi: 10.1016/0006-8993(83)91095-8.
The activities of two enzymes of the serotonin biosynthetic pathway, namely tryptophan hydroxylase (TPH) and 5-hydroxytryptophan-decarboxylase (5-HTP-D), were determined in the cockroach, Periplaneta americana, brain using radiometric techniques, significant levels of both enzymes were found. p-Chlorophenylalanine (PCPA) inhibited brain TPH activity strongly both in vitro and in vivo. In vitro, 10 mM PCPA reduced the TPH activity by 76% and in vivo either 15 micrograms/g or 30 micrograms/g of PCPA inhibited brain TPH activity by 80-85%. The activity of 5-HTP-D enzyme was inhibited significantly in vivo by 3-hydroxybenzylhydrazine, commonly known as NSD-1015. A recovery in the activity of 5-HTP-D enzyme was observed 12 h after 50 micrograms/g of NSD-1015 but 100 micrograms/g caused an inhibition lasting for the 24 h period studied.
利用放射性技术测定了美洲大蠊大脑中血清素生物合成途径的两种酶，即色氨酸羟化酶（TPH）和5-羟色氨酸脱羧酶（5-HTP-D）的活性，发现这两种酶均有显著水平。对氯苯丙氨酸（PCPA）在体外和体内均强烈抑制大脑TPH活性。在体外，10 mM PCPA使TPH活性降低76%，在体内，15微克/克或30微克/克的PCPA抑制大脑TPH活性80 - 85%。5-HTP-D酶的活性在体内被通常称为NSD-1015的3-羟基苄肼显著抑制。在给予50微克/克的NSD-1015后12小时观察到5-HTP-D酶活性恢复，但100微克/克导致在所研究的24小时内持续抑制。
