PROPERTIES OF RAT ADRENAL ZONA RETICULARIS CELLS: PRODUCTION AND STIMULATION OF CERTAIN STEROIDS

1979 ◽  
Vol 83 (3) ◽  
pp. 435-447 ◽  
Author(s):  
J. B. G. BELL ◽  
R. P. GOULD ◽  
P. J. HYATT ◽  
J. F. TAIT ◽  
S. A. S. TAIT
Keyword(s):  
Adrenal Cortex ◽  
Significant Role ◽  
Zona Fasciculata ◽  
Cell Type ◽  
Acth Stimulation ◽  
Specific Stimulus ◽  
Zona Reticularis ◽  
Cell Pool ◽  
Stimulation Of

The outputs of corticosterone, deoxycorticosterone and androstenedione from dispersed, purified rat adrenal zona reticularis and zona fasciculata cells have been measured by radioimmunoassay. Preferential production of deoxycorticosterone by zona reticularis cells was demonstrated by their higher basal deoxycorticosterone: corticosterone ratio when compared with zona fasciculata cells. Adrenocorticotrophin (ACTH) stimulated corticosterone output by all cell pools prepared by unit gravity (1 g) sedimentation, zona fasciculata cells being stimulated 130-fold compared with 20-fold for the zona reticularis cells in relation to their basal corticosterone output. In every cell pool, ACTH stimulated the output of corticosterone more than it stimulated the output of deoxycorticosterone. In parallel cell preparations, it was shown that ACTH increased the conversion of tracer amounts of radioactive deoxycorticosterone to corticosterone and decreased the conversion of radioactive corticosterone to 11-dehydrocorticosterone. Adrenocorticotrophin did not increase the conversion of radioactive deoxycorticosterone to total 11-oxygenated steroids (corticosterone+ 11-dehydrocorticosterone). It is unlikely therefore that ACTH stimulates 11 β-hydroxylation. Data indicate that the ratio of deoxycorticosterone to total 11-oxygenated steroids (corticosterone +11-dehydrocorticosterone) is characteristic for each cell type, and that this ratio will be relatively independent of ACTH stimulation or the amount of pregnenolone substrate available. Basal androstenedione outputs were similar for both types of cell, and ACTH stimulation was very small, being slightly greater for zona fasciculata than for zona reticularis cells. The contribution of the zona reticularis cells to the basal output of any steroid by the cells of the inner two zones of the adrenal cortex of the rat was relatively small (20% for deoxycorticosterone and 10% for corticosterone) and was even less after stimulation by ACTH. Unless a specific stimulus can be found, therefore, a significant role for the zona reticularis cannot yet be established.

scholarly journals IDENTIFICATION OF PEROXISOMES IN THE RAT ADRENAL CORTEX

1972 ◽  
Vol 20 (3) ◽  
pp. 173-179 ◽  
Author(s):  
MARGARET E. BEARD
Keyword(s):  
Acid Phosphatase ◽  
Adrenal Cortex ◽  
Zona Fasciculata ◽  
Positive Staining ◽  
Staining Reaction ◽  
Dense Matrix ◽  
Zona Reticularis ◽  
Liver And Kidney ◽  
Branched Structures ◽  
Electron Dense Matrix

Organelles with the ultrastructure and cytochemical characteristics of peroxisomes (microbodies) have been identified in cells of the zona fasciculata and zona reticularis of the rat adrenal cortex. These peroxisomes appear as small, elliptical to spherical or branched structures, enclosed by a single membrane and composed of a moderately electron-dense matrix. They do not possess a nucleoid or core of the type found in peroxisomes of liver and kidney. These organelles show a strongly positive staining reaction with the diaminobenzidine technique for peroxidatic activity of catalase. This staining is inhibited by aminotriazole. In cytochemical preparations revealing acid phosphatase activity, lysosomes are strongly stained and peroxisomes are free of reaction product.

scholarly journals Adrenal Gland Toxicity: Chemically Induced Dysfunction

1988 ◽  
Vol 7 (1) ◽  
pp. 45-69 ◽  
Author(s):  
H. D. Colby
Keyword(s):  
Adrenal Cortex ◽  
Covalent Binding ◽  
Critical Role ◽  
Physiological Role ◽  
Metabolic Activation ◽  
Zona Fasciculata ◽  
Zona Reticularis ◽  
Hormone Synthesis ◽  
Chemically Induced ◽  
Endocrine Organs

Among the endocrine organs, the adrenal cortex appears to be the most vulnerable to chemically induced injury. A wide variety of chemicals has been found to cause morphological or functional lesions in the gland. Some of the lesions are highly localized to specific anatomical zones of the adrenal cortex, and the resulting functional deficits depend on the physiological role(s) of the zone affected. In addition, metabolic activation is an important factor contributing to the gland's vulnerability to chemical injury. For example, carbon tetrachloride (CCl4) causes adrenocortical necrosis, but only of the innermost zone of the gland, the zona reticularis. The apparent reason for the localized effect of CCl4 in the adrenal cortex is that only the cells of the zona reticularis have the enzymatic capacity to activate CCl4, resulting in lipid peroxidation and covalent binding to cellular macromolecules. By contrast, the mineralocorticoid antagonist, spironolactone, causes functional lesions in the adrenal cortex that are limited to the middle zone of the gland, the zona fasciculata. The explanation again involves metabolic activation; only the zona fasciculata converts spironolactone to a highly reactive metabolite that effects the destruction of several enzymes that are required for steroid hormone synthesis. These findings indicate that bioactivation plays a critical role in the mechanism(s) of action of various toxic agents on the adrenal cortex and also may be responsible for the anatomically localized effects of many chemicals.

STIMULATION OF ADRENAL 5-ENE,3β-HYDROXYSTEROID DEHYDROGENASE BY CORTICOTROPHIN IN VITRO

1978 ◽  
Vol 78 (3) ◽  
pp. 457-458 ◽  
Author(s):  
N. LOVERIDGE ◽  
W. R. ROBERTSON
Keyword(s):  
Adrenal Gland ◽  
Hydroxysteroid Dehydrogenase ◽  
Cellular Biology ◽  
Zona Fasciculata ◽  
Zona Reticularis ◽  
Cytochemical Bioassay ◽  
Low Concentrations ◽  
Kennedy Institute ◽  
Stimulation Of

Division of Cellular Biology, The Mathilda and Terence Kennedy Institute of Rheumatology, Bute Gardens, London, W6 7DW (Received 24 April 1978) It is well established (Chayen, Daly, Loveridge & Bitensky, 1976) that segments of guineapig adrenal gland can be maintained in vitro and will respond to low concentrations (0·005– 5·0 pg/ml) of corticotrophin (ACTH). The response measured in the cytochemical bioassay of ACTH is the loss of ascorbate from the zona reticularis (Chayen, Loveridge & Daly, 1972), which is directly related to secretion of cortisol by these segments (Chayen, Bitensky, Chambers, Loveridge & Daly, 1974). However, because both major zones of the adrenal cortex are involved in steroidogenesis (see, e.g., Symington, 1969; Hyatt, Bell, Gould, Tait & Tait, 1976), the lack of a response in the zona fasciculata seems to be anomalous. To test whether the cells of the zona fasciculata in guinea-pig adrenal segments can respond to low concentrations

STUDIES ON CYCLIC NUCLEOTIDES IN THE ADRENAL GLAND

1979 ◽  
Vol 90 (1) ◽  
pp. 139-146 ◽  
Author(s):  
Sumio Shima ◽  
Yoshiko Kawashima ◽  
Masanao Hirai
Keyword(s):  
Cyclic Amp ◽  
Adrenal Cortex ◽  
Calcium Ionophore ◽  
Extracellular Calcium ◽  
Zona Fasciculata ◽  
Acth Stimulation ◽  
Steroid Production ◽  
Low Concentrations ◽  
Cyclic Amp Accumulation ◽  
High Concentrations

ABSTRACT Effects of ACTH and calcium on cyclic AMP and steroid production by the zona fasciculata-reticularis (the decapsulated fraction) from the rat adrenal cortex have been studied. Increasing concentrations of extracellular calcium enhanced the action of ACTH on cyclic AMP and steroid production. These effects of ACTH with calcium were prevented by lanthanum, but not by tetracaine or verapamil, suggesting that ACTH stimulation may be mediated by calcium through a process not involving the tetracaine- or verapamil-vulnerable step(s) of the calcium current. High concentrations of external calcium itself increased cyclic AMP accumulation without any increase in steroidogenesis. A calcium ionophore, X537A was stimulatory for steroidogenesis but inhibitory with respect to cyclic AMP accumulation. Considered together with the findings of steroidogenic stimulation by low concentrations of ACTH without cyclic AMP increase, these results suggest that ACTH primarily increases intracellular calcium mobilization thus stimulating directly the steroidogenesis, which is independent of the cyclic AMP system. Relatively high concentrations of ACTH activate the adenylate cyclase, which depends on extracellular calcium to increase cyclic AMP levels and stimulation of steroidogenesis by the decapsulated fractions of the adrenal cortex.

THE ROLE OF PROGESTERONE IN THE BIOSYNTHESIS OF CORTISOL IN HUMAN ADRENAL TISSUE

1968 ◽  
Vol 41 (3) ◽  
pp. 319-326 ◽  
Author(s):  
E. H. D. CAMERON ◽  
M. A. BEYNON ◽  
K. GRIFFITHS
Keyword(s):  
Adrenal Cortex ◽  
Biosynthetic Pathway ◽  
Zona Fasciculata ◽  
Relative Importance ◽  
Mathematical Approach ◽  
Zona Reticularis ◽  
Adrenal Tissue

SUMMARY The ability of cells from the zona fasciculata and the zona reticularis of the human adrenal cortex to transform labelled pregnenolone and progesterone to cortisol in vitro was investigated. Examination of the 3H:14C ratios of 16α-hydroxyprogesterone, 17α-hydroxyprogesterone, 11-deoxycorticosterone and cortisol formed during incubations in vitro suggested that the role of progesterone in the transformation of pregnenolone to cortisol might be a relatively minor one. An attempt was subsequently made to estimate the relative importance of the biosynthetic pathway to cortisol by way of progesterone in hyperplastic adrenal tissue by a mathematical approach.

OUTPUT OF OESTROGENS, TESTOSTERONE AND THEIR PRECURSORS BY ISOLATED HUMAN ADRENAL CELLS AS COMPARED WITH THAT OF GLUCOCORTICOSTEROIDS

1976 ◽  
Vol 71 (2) ◽  
pp. 219-229 ◽  
Author(s):  
V. KEYMOLEN ◽  
P. DOR ◽  
A. BORKOWSKI
Keyword(s):  
Adrenal Cortex ◽  
Acth Stimulation ◽  
Adrenal Cells ◽  
Selective Stimulation ◽  
Order Of Magnitude ◽  
Adrenal Secretion ◽  
Free Steroid ◽  
Stimulation Of ◽  
Sigmoid Shape

SUMMARY The output of oestrogens, testosterone and their precursors was compared with that of glucocorticosteroids under standardized conditions, in a suspension of isolated human adrenal cells. Cortisol, corticosterone, androstenedione, dehydroepiandrosterone and its sulphate all increased in the same proportions after ACTH stimulation. The response to the logarithm of ACTH concentrations had a sigmoid shape but was fairly linear between 5 and 100 to 1000 μu./ml. The output of dehydroepiandrosterone plus that of its sulphate was of the same order of magnitude as the production of cortisol; the output of free dehydroepiandrosterone averaged half that of the sulphate indicating that the adrenal cortex is capable, under certain conditions, of producing large amounts of the free steroid. The output of androstenedione was very low, on average 35 times lower than that of cortisol, suggesting by extrapolation that the adrenal secretion may not be the main source of androstenedione in vivo or that ACTH is not the unique stimulus to adrenal androstenedione secretion. The output of testosterone was small to negligible and that of oestrogens was practically absent. In three additional experiments the influence of prolactin, prostaglandins, FSH and HCG was explored: no selective stimulation of androgen or oestrogen output was observed except in one experiment in which HCG stimulated adrenal testosterone production.

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