Biomaterial Database

ACTH-induced increases in rabbit adrenal immunoreactive P-450(17 alpha) and P-450(21). 1990

M L Chouinard, and H R Fevold

Department of Chemistry, University of Montana, Missoula 59812.

Rabbit adrenal 17 alpha-hydroxylase activity has previously been shown to increase dramatically following ACTH stimulation. The present study was designed to determine whether the increase in enzyme activity could be correlated with an increase in P-450(17 alpha) protein measured by immunoblotting using an anti-porcine P-450(17 alpha) antibody. It was found that the total and specific contents of rabbit adrenal immunoreactive P-450(17 alpha) were increased 6- to 8-fold and 4-fold, respectively, after ACTH stimulation. The results were similar whether the detection system was 125I-labeled protein A or an alkaline phosphatase-conjugated second antibody. Corresponding increases in 17 alpha-hydroxylase activity were also observed but were slightly less than the increases in immunoreactive P-450(17 alpha), suggesting that not all of the protein was enzymatically active. Comparatively, immunoreactive P-450(21) was increased only 1.3-fold. Antibodies to porcine P-450(17 alpha) and bovine P-450(21) reacted monospecifically with the homologous rabbit and guinea pig proteins as judged by the detection of single bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Inhibition studies showed that in an assay using 125 micrograms per ml of microsomal protein ACTH-stimulated rabbit adrenal 17 alpha-hydroxylase activity was inhibited 72% at a 100 mg per ml concentration of the anti-porcine P-450(17 alpha); however, 47% inhibition was observed at the same concentration of anti-bovine P-450(21). Pre-immune IgG had no effect. Molecular weight, Mr, determinations by SDS-PAGE showed both rabbit and guinea pig P-450(17 alpha) to be 52 kDa; rabbit P-450(21), 54 kDa; and guinea pig P-450(21), 49 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D003720	Densitometry	The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.	Densitometries
D004797	Enzyme-Linked Immunosorbent Assay	An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.	ELISA,Assay, Enzyme-Linked Immunosorbent,Assays, Enzyme-Linked Immunosorbent,Enzyme Linked Immunosorbent Assay,Enzyme-Linked Immunosorbent Assays,Immunosorbent Assay, Enzyme-Linked,Immunosorbent Assays, Enzyme-Linked
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D000311	Adrenal Glands	A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.	Adrenal Gland,Gland, Adrenal,Glands, Adrenal
D000324	Adrenocorticotropic Hormone	An anterior pituitary hormone that stimulates the ADRENAL CORTEX and its production of CORTICOSTEROIDS. ACTH is a 39-amino acid polypeptide of which the N-terminal 24-amino acid segment is identical in all species and contains the adrenocorticotrophic activity. Upon further tissue-specific processing, ACTH can yield ALPHA-MSH and corticotrophin-like intermediate lobe peptide (CLIP).	ACTH,Adrenocorticotropin,Corticotropin,1-39 ACTH,ACTH (1-39),Adrenocorticotrophic Hormone,Corticotrophin,Corticotrophin (1-39),Corticotropin (1-39),Hormone, Adrenocorticotrophic,Hormone, Adrenocorticotropic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013250	Steroid Hydroxylases	Cytochrome P-450 monooxygenases (MIXED FUNCTION OXYGENASES) that are important in steroid biosynthesis and metabolism.	Steroid Hydroxylase,Steroid Monooxygenases,Hydroxylase, Steroid,Hydroxylases, Steroid,Monooxygenases, Steroid
D013254	Steroid 17-alpha-Hydroxylase	A microsomal cytochrome P450 enzyme that catalyzes the 17-alpha-hydroxylation of progesterone or pregnenolone and subsequent cleavage of the residual two carbons at C17 in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP17 gene, generates precursors for glucocorticoid, androgen, and estrogen synthesis. Defects in CYP17 gene cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL) and abnormal sexual differentiation.	17 alpha-Hydroxylase,17,20-Lyase,CYP17,Cytochrome P-450(17 alpha),P450(c17),Steroid 17 alpha-Monooxygenase,Steroid 17-Hydroxylase,Steroid 17-Monooxygenase,17 alpha-Hydroxylase Cytochrome P-450,17 alpha-Hydroxyprogesterone Aldolase,17,20-Desmolase,Cytochrome P-450(17-alpha),Cytochrome P450(17 alpha),Hydroxyprogesterone Aldolase,Steroid 17 alpha-Hydroxylase,Steroid-17-Hydroxylase,17 alpha Hydroxylase,17 alpha Hydroxylase Cytochrome P 450,17 alpha Hydroxyprogesterone Aldolase,17 alpha-Hydroxylase, Steroid,17 alpha-Monooxygenase, Steroid,17,20 Desmolase,17,20 Lyase,17-Hydroxylase, Steroid,17-Monooxygenase, Steroid,17-alpha-Hydroxylase, Steroid,Aldolase, 17 alpha-Hydroxyprogesterone,Aldolase, Hydroxyprogesterone,Steroid 17 Hydroxylase,Steroid 17 Monooxygenase,Steroid 17 alpha Hydroxylase,Steroid 17 alpha Monooxygenase,alpha-Hydroxyprogesterone Aldolase, 17,alpha-Monooxygenase, Steroid 17