scholarly journals Endothelium-Derived Steroidogenic Factor Enhances Angiotensin II-Stimulated Aldosterone Release by Bovine Zona Glomerulosa Cells

Endocrinology ◽  
2007 ◽  
Vol 148 (1) ◽  
pp. 317-323 ◽  
Author(s):  
Craig J. Hanke ◽  
Blythe B. Holmes ◽  
Yafei Xu ◽  
Kasem Nithipatikom ◽  
William B. Campbell
Keyword(s):  
Mass Spectrometry ◽  
Endothelial Cells ◽  
Angiotensin Ii ◽  
Adrenal Gland ◽  
Synergistic Effect ◽  
Zona Glomerulosa ◽  
Angiotensin Iv ◽  
Anatomical Relationship ◽  
Glomerulosa Cells ◽  
Zona Glomerulosa Cells

Endothelium-derived steroidogenic factor (EDSF) is an endothelial peptide that stimulates aldosterone release from bovine adrenal zona glomerulosa (ZG) cells. The regulation of aldosterone release by combinations of EDSF and angiotensin II (AII) or EDSF and ACTH was investigated. Endothelial cells (ECs) and EC-conditioned media (ECCM) increased aldosterone release from ZG cells, an activity attributed to EDSF. AII (10−12 to 10−8m) and ACTH (10−12 to 10−9m) also stimulated the release of aldosterone from ZG cells. The stimulation by AII, but not ACTH, was greatly enhanced when ZG cells were coincubated with ECs. AII was metabolized by ECs to peptides identified by mass spectrometry as angiotensin (1-7) and angiotensin IV. There was very little metabolism of AII by ZG cells. Neither of these two AII metabolites altered aldosterone release from ZG cells, so they could not account for the enhanced response with ECs. AII-induced aldosterone release from ZG cells was enhanced by ECCM but not cell-free conditioned medium. This enhanced response was not due to increased EDSF release from ECs by AII. The synergistic effect of EDSF and AII was apparent when AII was added during or after the generation of ECCM and not observed when the AII component of the enhancement was blocked by the AII antagonist, losartan. These studies indicate that EDSF enhances the steroidogenic effect of AII. In the adrenal gland, ECs are in close anatomical relationship with ZG cells and may sensitize ZG cells to the steroidogenic action of AII by releasing EDSF.

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

1974 ◽  
Vol 185 (1081) ◽  
pp. 375-407 ◽  
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.

Inhibition of aldosterone release by hypoxia in vitro: interaction with carbon monoxide

1994 ◽  
Vol 76 (2) ◽  
pp. 689-693 ◽  
Author(s):  
H. Raff ◽  
B. Jankowski
Keyword(s):  
Carbon Monoxide ◽  
Angiotensin Ii ◽  
Zona Glomerulosa ◽  
Michaelis Constant ◽  
Aldosterone Synthase ◽  
Aldosterone Production ◽  
Glomerulosa Cells ◽  
In Vitro Interaction ◽  
Zona Glomerulosa Cells

We have demonstrated that the aldosteronogenic pathway of the zona glomerulosa is unusually sensitive to modest changes in PO2 (Michaelis constant for O2 approximately 95 Torr). The current study evaluated the interaction of CO (the classic ligand for P-450 enzymes) and the decreases in O2 on aldosteronogenesis in vitro. Bovine adrenocortical zona glomerulosa cells were incubated for 2 h and stimulated with either adenosine 3′,5′-cyclic monophosphate (cAMP) or angiotensin II. Ten and 20% CO led to significant decreases in cAMP- and angiotensin II-stimulated aldosteronogenesis. The combination of 20% CO and moderate decreases in PO2 (from approximately 140 to approximately 100 Torr) led to an interactive decrease in aldosterone production. The conversion of corticosterone to aldosterone catalyzed by aldosterone synthase, which is the site of O2 sensitivity, was not significantly inhibited by CO. We conclude that the aldosterone pathway is not exceptionally sensitive to CO compared with other steroidogenic pathways. This observation suggests that the unique O2-sensitive properties of the aldosterone pathway located primarily within aldosterone synthase may not reside in its CO binding site (i.e., heme).

An ultrastructural stereologic study of the effects of angiotensin II on the zona glomerulosa of rat adrenal cortex

1980 ◽  
Vol 95 (4) ◽  
pp. 523-527 ◽  
Author(s):  
Giuseppina Mazzocchi ◽  
Piera Rebuffat ◽  
Anna S. Belloni ◽  
Claudia Robba ◽  
Gastone G. Nussdorfer
Keyword(s):  
Angiotensin Ii ◽  
Smooth Endoplasmic Reticulum ◽  
Zona Glomerulosa ◽  
Significant Rise ◽  
Immunological Methods ◽  
Short Term ◽  
Plasma Aldosterone Concentration ◽  
Noticeable Increase ◽  
Glomerulosa Cells ◽  
Zona Glomerulosa Cells

Abstract. The effects of angiotensin II on the rat zona glomerulosa were investigated by morphometric and radio-immunological methods. Short-term (l h) angiotensin-administration induced lipid depletion in zona glomerulosa cells and a significant rise in the plasma aldosterone concentration. Chronic angiotensin-treatment provoked a noticeable increase in the volume of the zona glomerulosa and its cells, which was mainly due to the hypertrophy of smooth endoplasmic reticulum and mitochondrial compartment. In chronically treated animals the output of aldosterone in response to a short-term stimulation with angiotensin II displayed a significant increase. These findings are interpreted as indicating that angiotensin II is involved in the stimulation of the growth and steroidogenic capacity of the rat zona glomerulosa.

Detection of angiotensin II binding to single adrenal zona glomerulosa cells by confocal Raman microspectroscopy

1999 ◽  
Author(s):  
Michael J. McCoy ◽  
Timothy J. Habermann ◽  
Craig J. Hanke ◽  
Fran Adar ◽  
William B. Campbell ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Zona Glomerulosa ◽  
Raman Microspectroscopy ◽  
Confocal Raman Microspectroscopy ◽  
Glomerulosa Cells ◽  
Confocal Raman ◽  
Zona Glomerulosa Cells

Long-term effects of ACTH combined with angiotensin II on steroidogenesis and adrenal zona glomerulosa morphology in the rat

1987 ◽  
Vol 114 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Anne M. Riondel ◽  
Piera Rebuffat ◽  
Giuseppina Mazzochi ◽  
Gastone G. Nussdorfer ◽  
Rolf C. Gaillard ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Morphological Changes ◽  
Zona Glomerulosa ◽  
Zona Fasciculata ◽  
Homogeneous Population ◽  
Long Term Treatment ◽  
Acth Treatment ◽  
Glomerulosa Cells ◽  
Zona Glomerulosa Cells

Abstract. To test the hypothesis that the trophic action of angiotensin II on the adrenal zona glomerulosa may allow a sustained stimulation of aldosterone by ACTH by preventing the morphological changes of the zona glomerulosa cells into zona fasciculata-like elements we investigated the effects in rats of a 6-day treatment with ACTH (100 μg/kg/day) alone or combined with angiotensin II (300 ng/kg/day) on corticosterone and aldosterone production and adrenal morphology. The responsiveness of both steroids to an acute ACTH dose was also studied on the last day of long-term treatment. Morphologic data showed that prolonged ACTH treatment stimulated the growth of zona glomerulosa cells, though it transformed the tubulo-lamellar cristae of mitochondria into a homogeneous population of vesicles. Angiotensin II furthered the trophic effects of ACTH but prevented the mitochondrial transformation. Despite its ability to conserve the well differentiated aspect of the zona glomerulosa cells, the administration of angiotensin II was unable to prevent the fall in the secretion of aldosterone caused by chronic ACTH treatment and its subsequent unresponsiveness to ACTH stimulation.

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