Dept. of Internal Medicine (내과학); Dept. of Obstetrics & Gynecology (산부인과학)
P-450c17; hydroxylase; Homozygote
School of Medicine
대한내분비학회지, Vol.11(1) : 102-107, 1996
The single enzyme P-450c17 hydroxylase catalyzes the 17α-hydroxylation of both pregnenolone and progesterone and the side-chain cleavage of 17α-hydroxypregnenolone and 17α-hydroxypro- gesterone to dehydroepiandrosterone and androstenedione. This enzyme is located in the endoplasmic reticulum and consists of a P-450c17 and a specific flavoprotein NADPH-cytochrome P-450 reductase. The clinical picture and hormonal pattern in 17α-hydroxylase deficiency have been consistent in both genotypic sexes with hypergonadotropic hypogonadism in whom the virtual absence of gonadal steroids results in a female phenotype with primary amenorrhea and pseudohermaphro- ditism in the male and underdeveloped secondary sex characteristics and hypermineralocorticoidism with hypertension, hypokalemia, suppressed renin-angiotensin system and extremely reduced aldo-sterone production. A 17-year-old girl visited endocrine clinic because of amenorrhea, absence of pubic and axillary hair, and hypertension. she had elevated levels of serum corticosterone, deoxycorticosterone(DOC), 18-hydroxycorticosterone(18-OHB). Stumulation with ACTH effected minimal increase in the elevated steroids and the ACTH-stimulated 18-OHB to aldosterone ratio was more than 280. These hormonal patterns appear to be homozygote in 17α-hydroxylase deficiency.