Phenylketonuria (PKU) is the most common autosomal recessive disorder of amino acid metabolism. Thedisease is caused mainly by mutations in the phenylalanine hydroxylase (PAH) gene, encoding phenylalaninehydroxylase (PAH) enzyme. The PAH enzyme deficiency results in the elevation of phenylalanine inthe blood, which may cause severe irreversible mental retardation in the affect...

A selection procedure was devised for neurons and related cells that depends upon the ability of the cells to synthesize certain amine neurotransmitters. The rationale for selection is that tyrosine is an essential amino acid for most mammalian cells and that three enzymes from mammalian sources can catalyze the synthesis of tyrosine: phenylalanine hydroxylase (EC 1.14.16.1), tyrosine hydroxyla...

T he enzyme dopamine b hydroxylase (EC 1.14.17.1, MIM 223360) is a monooxygenase that catalyses the conversion of dopamine to norepinephrine. It requires copper as a cofactor and uses oxygen and ascorbate as cosubstrates. Dopamine b hydroxylase is localised within the soluble and membrane fractions of secretory vesicles of neurones of the central nervous system that produce epinephrine and nore...

Rats were given intraperitoneal injections of 2 mCi of carrier-free "Pi and substances known to activate liver phenylalanine hydroxylase. After 30 min, these animals were anesthetized and their livers removed for analysis of enzyme activity, 32Pi ncorporation into immunoprecipitated phenylalanine hydroxylase and [yS2P]ATP specific activity. Following glucagon treatment, rat liver phenylalanine ...

phenylketonuria (pku) is one of the most common metabolic inborn diseases caused by mutations in the phenylalanine hydroxylase (pah) gene. this gene is linked to a variable number of tandem repeats (vntr) region which is a polymorphic marker that facilitates the implementation of prenatal diagnosis and carrier screening. in this study, vntr with 13 repeats that has not been reported previously ...

congenital adrenal hyperplasia comprises a group of disorders resulting from defects in enzymes required for the synthesis of cortisol. the clinical presentation depends on the specific enzyme defect. we report a rare case of congenital adrenal hyperplasia due to 17 alpha-hydroxylase deficiency. a 26-year-old female patient referred with hypertension and hypokalemia. she also had primary amenor...

We previously reported that a factor(s) from rat choriocarcinoma (Rcho-1) cells suppresses circulating PRL levels and increases tyrosine hydroxylase activity in tuberoinfundibular dopaminergic neurons in vivo. The purposes of this study were to determine whether this factor(s) increases tyrosine hydroxylase activity in fetal hypothalamic cells in vitro and to evaluate its chemical nature. The R...

Aryl hydroxylase, derived from hamster fetus cells grown in culture, is an inducible microsomal enzyme system which requires NADPH and molecular oxygen. The addition of benz[u]anthracene or other polycyclic hydrocarbons to the culture medium causes significant increases in the amount of hydroxylase activity: after a lag period of 35 min, the level of hydroxylase activity increases linearly for ...