Mullins, LJ and Peter, A and Wrobel, N and McNeilly, J R and McNeilly, A S and Al-Dujaili, Emad A S and Brownstein, D G and Mullins, J J and Kenyon, CJ (2008) Cyp11b1 Null Mouse, a Model of Congenital Adrenal Hyperplasia. Journal of Biological Chemistry, 284 (6). pp. 3925-3934. ISSN 0021-9258Full text not available from this repository. (Request a copy)
Patients with congenital adrenal hyperplasia arising from mutations of 11β-hydroxylase, the final enzyme in the glucocorticoid biosynthetic pathway, exhibit glucocorticoid deficiency, adrenal hyperplasia driven by unsuppressed hypothalamo-pituitary-adrenal activity, and excess mineralocorticoid activity caused by the accumulation of deoxycorticosterone. A mouse model, in which exons 3-7 of Cyp11b1 (the gene encoding 11β-hydroxylase) were replaced with cDNA encoding enhanced cyan fluorescent protein, was generated to investigate the underlying disease mechanisms. Enhanced cyan fluorescent protein was expressed appropriately in the zona fasciculata of the adrenal gland, and targeted knock-out was confirmed by urinary steroid profiles and, immunocytochemically, by the absence of 11β-hydroxylase. The null mice exhibited glucocorticoid deficiency, mineralocorticoid excess, adrenal hyperplasia, mild hypertension, and hypokalemia. They also displayed glucose intolerance. Because rodents do not synthesize adrenal androgens, changes in reproductive function such as genital virilization of females were not anticipated. However, adult homozygote females were infertile, their ovaries showing an absence of corpora lutea and a central proliferation of disorganized steroidogenic tissue. Null females responded normally to superovulation, suggesting that raised systemic progesterone levels also contribute to infertility problems. The model reveals previously unrecognized phenotypic subtleties of congenital adrenal hyperplasia.
|Divisions:||School of Health Sciences > Dietetics, Nutrition and Biological Sciences|
|Date Deposited:||04 Nov 2009 11:59|
|Last Modified:||26 Feb 2011 12:41|
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