Gene expression profile in rat adrenal zona glomerulosa cells stimulated with aldosterone secretagogues

The mineralocorticoid aldosterone, mainly produced by the adrenal gland, is essential for life, but an abnormally excessive secretion causes severe pathological effects including hypertension and target organ injury in the heart and kidney. The aim of this study was to determine the gene regulatory network triggered by aldosterone secretagogues in a nontransformed cell system. Freshly isolated rat adrenal zona glomerulosa cells were stimulated with the two main aldosterone secretagogues, angiotensin II and potassium, for 2 h and subjected to whole genome expression studies using multiple biological and bioinformatics tools. Several genes were differentially expressed by ANG II ( n = 133) or potassium ( n = 216). Genes belonging to the nucleic acid binding and transcription factor activity categories were significantly enriched. A subset of the most regulated genes was confirmed by real-time RT-PCR, and then their expression was analyzed in time curve studies. Differentially expressed genes were grouped according to their time response expression pattern, and their promoter regions were analyzed for common regulatory transcription factor binding sites. Finally, data mining with gene promoters, transcription factors, and literature databases was performed to generate gene interaction networks for either ANG II or potassium. This paper provides for the first time a complete study of the genes that are regulated, and the interaction between them, by aldosterone secretagogues in rat adrenal cells. Increasing our knowledge of adrenal physiology and gene regulation in nontransformed cell systems could lead us to a better approach for the discovery of candidate genes involved in pathological conditions of the adrenal cortex.

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Zona glomerulosa cell responses to atrial natriuretic factor in genetically hypertensive rats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1986.251.4.h689 ◽

1986 ◽

Vol 251 (4) ◽

pp. H689-H692 ◽

Cited By ~ 1

Author(s):

K. Racz ◽

O. Kuchel ◽

N. T. Buu ◽

J. Gutkowska ◽

W. Debinski ◽

...

Keyword(s):

Target Cell ◽

Atrial Natriuretic Factor ◽

Inhibitory Action ◽

Zona Glomerulosa ◽

Cell Suspensions ◽

Ang Ii ◽

Hypertensive Rats ◽

Natriuretic Factor ◽

Glomerulosa Cells ◽

Zona Glomerulosa Cells

We examined whether abnormalities in target cell responsiveness to atrial natriuretic factor (ANF), similar to those previously found in the kidney, could also be present in the zona glomerulosa cells of spontaneously hypertensive rats (SHR) and salt-sensitive Dahl rats (S rats). We found an attenuated aldosterone (Aldo) response to angiotensin II (ANG II) in zona glomerulosa cell suspensions isolated from hypertensive SHR compared with those from Wistar-Kyoto (WKY) rats, whereas cells derived from hypertensive S rats showed a significantly higher Aldo response to the maximum stimulatory dose of ANG II than those from salt-resistant Dahl rats (R rats). The maximum observed Aldo responses to ACTH stimulation were not different in SHR or S rats compared with their respective controls. ANF exerted a potent inhibitory action on both ANG II- and ACTH-stimulated secretions of glomerulosa cell suspensions, without any difference in its potency between hypertensive and control rats. The equipotent inhibitory action of ANF on the ANG II- and ACTH-stimulated secretion of Aldo in those cell suspensions suggests that the previously observed alterations in the target cell responsiveness to ANF do not exist in the adrenal zona glomerulosa cells of SHR and Dahl S rats.

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Endothelial cell nitric oxide inhibits aldosterone synthesis in zona glomerulosa cells: modulation by oxygen

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.2000.279.4.e846 ◽

2000 ◽

Vol 279 (4) ◽

pp. E846-E854 ◽

Cited By ~ 18

Author(s):

Craig J. Hanke ◽

William B. Campbell

Keyword(s):

Nitric Oxide ◽

Cultured Cells ◽

Inhibitory Effect ◽

Zona Glomerulosa ◽

Ang Ii ◽

Low Oxygen ◽

Endogenous Nitric Oxide ◽

Glomerulosa Cells ◽

Deta Nonoate ◽

Zona Glomerulosa Cells

The regulation of aldosterone synthesis by endogenous nitric oxide (NO) was examined in cultured cells of the adrenal cortex. Endothelial NO synthase (eNOS) was detected by Western blot in cultured adrenal endothelial cells (ECs) but not in zona glomerulosa (ZG) cells or adrenal fibroblasts. Neither inducible (iNOS) nor neuronal NOS (nNOS) isoforms were detected in the cells. Only ECs had NOS activity and converted [3H]l-arginine to [3H]l-citrulline. Angiotensin II (ANG II, 100 nM) increased EC production of nitrate/nitrite by 2.4-fold. Coincubation with ECs or treatment with DETA nonoate increased the fluorescence of ZG cells loaded with an NO-sensitive dye, diaminofluorescein 2 diacetate (DAF-2 DA). DETA nonoate inhibited ANG II (1 nM) and potassium (10 mM) -stimulated aldosterone release in a concentration-related manner. This inhibitory effect of NO was enhanced >10-fold by decreasing the oxygen concentration from 21 to 8%. Coincubation of EC and ZG cells in 8% oxygen inhibited ANG II-induced aldosterone release, and inhibition was reversed by blockade of NOS. These findings indicate that adrenal EC-derived NO inhibits aldosterone release by cultured ZG cells and that the sensitivity to NO inhibition is increased at low oxygen concentrations.

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The properties of adrenal zona glomerulosa cells after purification by gravitational sedimentation

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1974.0025 ◽

1974 ◽

Vol 185 (1081) ◽

pp. 375-407 ◽

Cited By ~ 39

Keyword(s):

Angiotensin Ii ◽

Cyclic Amp ◽

Microscopic Examination ◽

Zona Glomerulosa ◽

Maximal Response ◽

Zona Fasciculata ◽

Gravitational Sedimentation ◽

Rat Adrenals ◽

Glomerulosa Cells ◽

Zona Glomerulosa Cells

The densities of latex spheres and biological cells can be reliably determined from their sedimentation rate in an albumin gradient under unit gravitational force. The densities of zona glomerulosa and fasciculata cells of rat adrenals were found to be 1.072 ± 0.004 and 1.040 ± 0.001 respectively. Purified zona glomerulosa cells of rat adrenals can be prepared by gravitational sedimentation of dispersed cells from capsule strippings of the gland, which originally contain 3 to10% zona fasciculata contamination. Electron and phase microscopic examination of the sedimented glomerulosa cells and their steroidogenic response to ACTH and cyclic AMP indicate that they are reasonably free of contamination from zona fasciculata cells. Electron microscopic examination of the purified glomerulosa cells indicates that most of them are reasonably normal in structure. Their basal production of corticosterone is decreased after sedimentation. However, their maximal response of corticosterone output to serotonin and potassium and their response to all potassium concentrations is not significantly altered, indicating normal function for the cells producing steroids. Their maximal responses to ACTH, valine angiotensin II and cyclic AMP are decreased, but, at the doses used, steroidogenesis by the zona fasciculata contamination in the unfractionated preparation would be stimulated by these substances. Purified zona glomerulosa cells have about the same maximal response of corticosterone output (about twofold) to potassium, valine and isoleucine angiotensin II, serotonin and ACTH. The maximal response of the purified zona glomerulosa cells to cyclic AMP is similar to that elicited by valine and isoleucine angiotensin II, potassium, serotonin or ACTH. This indicates that if these stimuli act by increasing cyclic AMP output, then the maximal response of corticosterone output (about twofold) is defined by the limited response of the biosynthetic pathways to cyclic AMP.

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