help button home button Endocrine Society Endocrinology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Raff, H.
Right arrow Articles by Oaks, M. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Raff, H.
Right arrow Articles by Oaks, M. K.
Endocrinology Vol. 140, No. 7 3147-3153
Copyright © 1999 by The Endocrine Society

ARTICLES

The Effect of Hypoxia from Birth on the Regulation of Aldosterone in the 7-Day-Old Rat: Plasma Hormones, Steroidogenesis in Vitro, and Steroidogenic Enzyme Messenger Ribonucleic Acid1

Hershel Raff, Barbara M. Jankowski, Eric D. Bruder, William C. Engeland and Martin K. Oaks

Endocrine (H.R., B.M.J., E.D.B.) and Immunology (M.K.O.) Research Laboratories, St. Luke’s Medical Center, Medical College of Wisconsin, Milwaukee, Wisconsin 53215; and the Department of Surgery, University of Minnesota Medical School (W.C.E.), Minneapolis, Minnesota 55455

Address all correspondence and requests for reprints to: Hershel Raff, Ph.D., St. Luke’s Health Science Building, 2901 West KK River Parkway, Suite 503, Milwaukee, Wisconsin 53215. E-mail: hraff{at}mcw.edu

Adaptation to hypoxia in the neonate requires an appropriate adrenocortical response. The purpose of this study was to examine the adaptation of the aldosterone pathway in rat pups exposed to hypoxia in vivo from birth to 7 days of age.

Neonatal rats (with their lactating dams) were exposed to normoxia (21% O2) or hypoxia (12% O2) continuously for 7 days from birth. Trunk blood was collected, and entire adrenal glands were processed from 7-day-old rats to study the activity of the steroidogenic pathway in dispersed cells and isolated mitochondria, for measurement of expression of the steroidogenic enzyme messenger RNAs (mRNAs) by RT-competitive PCR and in situ hybridization histochemistry, for measurement of zona glomerulosa width by immunohistofluorescent staining for P450c11AS protein, and for measurement of mitochondrial number and distribution by transmission electron microscopy.

Exposure to hypoxia for 7 days from birth resulted in a marked increase in plasma ACTH, corticosterone, and aldosterone with no change in PRA. Aldosteronogenesis and P450c11AS activity were both augmented in dispersed cells; this effect was lost in isolated mitochondria (from entire adrenal glands) using a permeable substrate for P450c11AS. There was no significant effect of hypoxia on expression of the steroidogenic enzyme mRNAs measured by RT-competitive PCR or in situ hybridization histochemistry. Finally, hypoxia had no effect on mitochondrial number or stereology as assessed by transmission electron microscopy or on zona glomerulosa width as assessed by staining for P450c11AS protein.

We conclude that, as opposed to that in adults, hypoxia in the neonate results in an augmentation of aldosteronogenesis. This effect is not accounted for by a change in steroidogenic enzyme mRNA expression, zona glomerulosa width (i.e. hyperplasia), or mitochondrial number or distribution. This functional augmentation of aldosteronogenesis may be due to a change in mitochondrial permeability to steroid substrates and/or the effect of cytosolic factors that control mitochondrial steroidogenesis.




This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
E. D. Bruder, J. K. Taylor, K. J. Kamer, and H. Raff
Development of the ACTH and corticosterone response to acute hypoxia in the neonatal rat
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2008; 295(4): R1195 - R1203.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. GenomicsHome page
E. D. Bruder, J. J. Lee, E. P. Widmaier, and H. Raff
Microarray and real-time PCR analysis of adrenal gland gene expression in the 7-day-old rat: effects of hypoxia from birth
Physiol Genomics, April 24, 2007; 29(2): 193 - 200.
[Abstract] [Full Text] [PDF]

Home page
 J EndocrinolHome page
E. D Bruder, L. Jacobson, and H. Raff
Plasma leptin and ghrelin in the neonatal rat: interaction of dexamethasone and hypoxia
J. Endocrinol., June 1, 2005; 185(3): 477 - 484.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
E. D. Bruder, P. C. Lee, and H. Raff
Dexamethasone treatment in the newborn rat: fatty acid profiling of lung, brain, and serum lipids
J Appl Physiol, March 1, 2005; 98(3): 981 - 990.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
E. D. Bruder, P. C. Lee, and H. Raff
Lipid and fatty acid profiles in the brain, liver, and stomach contents of neonatal rats: effects of hypoxia
Am J Physiol Endocrinol Metab, February 1, 2005; 288(2): E314 - E320.
[Abstract] [Full Text] [PDF]

Home page
 EndocrinologyHome page
E. D. Bruder, P. C. Lee, and H. Raff
Metabolic Consequences of Hypoxia from Birth and Dexamethasone Treatment in the Neonatal Rat: Comprehensive Hepatic Lipid and Fatty Acid Profiling
Endocrinology, November 1, 2004; 145(11): 5364 - 5372.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Endocrinol. Metab.Home page
E. D. Bruder, P. C. Lee, and H. Raff
Metabolomic analysis of adrenal lipids during hypoxia in the neonatal rat: implications in steroidogenesis
Am J Physiol Endocrinol Metab, May 1, 2004; 286(5): E697 - E703.
[Abstract] [Full Text] [PDF]

Home page
 EndocrinologyHome page
H. Raff, J. J. Lee, E. P. Widmaier, M. K. Oaks, and W. C. Engeland
Basal and Adrenocorticotropin-Stimulated Corticosterone in the Neonatal Rat Exposed to Hypoxia from Birth: Modulation by Chemical Sympathectomy
Endocrinology, January 1, 2004; 145(1): 79 - 86.
[Abstract] [Full Text] [PDF]

Home page
 Exp. Biol. Med.Home page
P. C. Lee, M. Struve, and H. Raff
Effects of Hypoxia on the Development of Intestinal Enzymes in Neonatal and Juvenile Rats
Experimental Biology and Medicine, June 1, 2003; 228(6): 717 - 723.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
E. D. Bruder, D. L. Ball, T. L. Goodfriend, and H. Raff
An oxidized metabolite of linoleic acid stimulates corticosterone production by rat adrenal cells
Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2003; 284(6): R1631 - R1635.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
H. Raff, J. J. Hong, M. K. Oaks, and E. P. Widmaier
Adrenocortical responses to ACTH in neonatal rats: effect of hypoxia from birth on corticosterone, StAR, and PBR
Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2003; 284(1): R78 - R85.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
P. C. Lee, B. Jelinek, M. Struve, E. D. Bruder, and H. Raff
Effect of neonatal hypoxia on the development of hepatic lipase in the rat
Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2000; 279(4): R1341 - R1347.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
H. Raff, E. D. Bruder, B. M. Jankowski, and T. L. Goodfriend
Neonatal hypoxic hyperlipidemia in the rat: effects on aldosterone and corticosterone synthesis in vitro
Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2000; 278(3): R663 - R668.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 1999 by The Endocrine Society