STEROID PRODUCTION IN VITRO BY THE OVARIES AND ADRENAL GLANDS OF THE THIRTEEN-LINED GROUND SQUIRREL (CITELLUS TRIDECEMLINEATUS MITCHELL)

1965 ◽  
Vol 32 (3) ◽  
pp. 401-402 ◽  
Author(s):  
G. P. VINSON
2006 ◽  
Vol 290 (1) ◽  
pp. E199-E203 ◽  
Author(s):  
Hershel Raff ◽  
Eric D. Bruder

The synthesis of adrenal steroids requires molecular oxygen. Because arterial hypoxemia is a common clinical condition, the purpose of the present study was to examine steroidogenesis in vitro under physiological changes in O2 tension (Po2) in cells from human adrenal glands with aldosterone-secreting adenomas (ASA; n = 3) or with bilateral adrenal hyperplasia causing Cushing's syndrome ( n = 4). A decrease in Po2 from 150 mmHg (mild hyperoxia) to 80 mmHg had minimal effect on steroid production. A reduction to 40 mmHg (still well within the physiological range) significantly inhibited cAMP- and ACTH-stimulated aldosterone, cortisol, and dehydroepiandrosterone (DHEA) production from ASA. Furthermore, cortisol and DHEA production in cells from histologically normal tissue, adjacent to ASA and from bilateral adrenal hyperplasias, was also inhibited under a Po2 of 40 mmHg. We conclude that physiological decreases in Po2 to levels typical for adrenal venous Po2 under mild hypoxia inhibit steroidogenesis. These studies may have implications for oxygen therapy in critically ill patients with functional adrenal insufficiency, as well as for therapeutic options in patients with adrenal neoplasms.


1959 ◽  
Vol 37 (1) ◽  
pp. 1255-1261 ◽  
Author(s):  
O. Héroux ◽  
E. Schönbaum

The rate of production of corticosteroids in vitro as well as the histological picture of the adrenal glands was studied in white rats exposed to cold for 3 months, either indoors at 6 °C in individual cages or outdoors during the winter in groups of 10.Under the indoor cold conditions, the adrenals hypertrophied within 1 week and their weight then remained constant for the following 11 weeks. The hypertrophy was due to an increase in the number of cells in the zona fasciculata. Relative to adrenal weight, the production of corticosteroids in vitro was less in the 6 °C rats than in the 30 °C controls. Under the outdoor cold conditions, the adrenal weight as well as the number of fasciculata cells remained normal, but the steroid production "in vitro" was greater than in the "summer controls". Since both "indoor" and "outdoor" cold-exposed rats have been shown previously to develop a similar degree of cold resistance as well as a similar capacity for elevating their metabolism through a non-shivering heat production mechanism, it appears that similar degrees of adaptation to cold can exist with different requirements of adrenocortical hormones.


1959 ◽  
Vol 37 (11) ◽  
pp. 1255-1261 ◽  
Author(s):  
O. Héroux ◽  
E. Schönbaum

The rate of production of corticosteroids in vitro as well as the histological picture of the adrenal glands was studied in white rats exposed to cold for 3 months, either indoors at 6 °C in individual cages or outdoors during the winter in groups of 10.Under the indoor cold conditions, the adrenals hypertrophied within 1 week and their weight then remained constant for the following 11 weeks. The hypertrophy was due to an increase in the number of cells in the zona fasciculata. Relative to adrenal weight, the production of corticosteroids in vitro was less in the 6 °C rats than in the 30 °C controls. Under the outdoor cold conditions, the adrenal weight as well as the number of fasciculata cells remained normal, but the steroid production "in vitro" was greater than in the "summer controls". Since both "indoor" and "outdoor" cold-exposed rats have been shown previously to develop a similar degree of cold resistance as well as a similar capacity for elevating their metabolism through a non-shivering heat production mechanism, it appears that similar degrees of adaptation to cold can exist with different requirements of adrenocortical hormones.


1972 ◽  
Vol 70 (4) ◽  
pp. 741-757
Author(s):  
Otto Linèt

ABSTRACT Rat adrenal glands atrophied by the administration of cortisol acetate in vivo were used as a model for the study of early metabolic processes occurring in vitro. Atrophied adrenals incubated in the presence of 14C-leucine incorporated subnormal quantities of this amino acid per mg of protein for the first 120 min. When the incubation lasted for a total period of 180 or 240 min a supranormal rise in the 14C-leucine incorporation was observed. Similar changes occurred with some delay with regard to corticosterone production as expressed per 100 mg of tissue. No differences in 14C-leucine incorporation were observed between the control and atrophied adrenals in vivo. Homogenates from atrophied glands incorporated 14C-leucine to a greater extent than the control homogenates. The in vitro incorporation of 14C-orotic acid into the RNA was also higher in atrophied adrenals. The in vitro use of actinomycin D, cycloheximide and amphenone indicated that corticosterone production depended on the incorporation of 14C-leucine. The addition of cortisol to the incubation media markedly decreased the enhancement of 14C-lysine incorporation into the protein of atrophied adrenals. These, as well as additional results suggest rebound phenomena: once atrophic adrenals are transferred to cortisol-free media, reparative processes begin after a delay period. Such phenomena seem to be mediated by regulatory mechanisms at the adrenal level.


1956 ◽  
Vol 92 (4) ◽  
pp. 855-859 ◽  
Author(s):  
C. J. P. Giroud ◽  
M. Saffran ◽  
A. V. Schally ◽  
J. Stachenko ◽  
E. H. Venning
Keyword(s):  

1962 ◽  
Vol 25 (2) ◽  
pp. 233-237 ◽  
Author(s):  
J. G. PHILLIPS ◽  
I. CHESTER JONES ◽  
D. BELLAMY

SUMMARY Adrenal glands of lizards (Lacerta viridis L.) and snakes (Natrix natrix L.) were incubated in media containing tritiated progesterone. Aldosterone, corticosterone and an unknown steroid were produced. Added ACTH did not affect, though added amphenone markedly reduced, the rate of steroid production.


1978 ◽  
Vol 79 (3) ◽  
pp. 393-394 ◽  
Author(s):  
R. GUNASEGARAM ◽  
K. L. PEH ◽  
P. C. T. CHEW ◽  
S. M. M. KARIM ◽  
S. S. RATNAM

Department of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospitalfor Women, Singapore 8, Republic of Singapore (Received 3 May 1978) From the previous studies of Bloch & Benirschke (1959, 1962) and Plotz, Kabara, Davis, LeRoy & Gould (1968) it appears that at mid-term, human foetal adrenal glands are capable of synthesizing C21- and C19-steroids de novo from acetate and cholesterol. Villee, Engel, Loring & Villee (1961), however, incubated slices and homogenates of foetal adrenal gland with [2-14C]acetate or [4-14C]cholesterol and could not demonstrate the incorporation of radioactivity into these steroids. Moreover, perfusion studies by three groups of investigators indicated only minute conversions of the same radioactive substrates into neutral steroids in the foetal adrenal glands (Solomon, Bird, Ling, Iwamiya & Young, 1967; Telegdy, Weeks, Archer, Wiqvist & Diczfalusy, 1970a; Telegdy, Weeks, Lerner, Stakemann & Diczfalusy, 1970b). It is widely believed that steroid hormones are normally synthesized from acetate via


1970 ◽  
Vol 118 (2) ◽  
pp. 283-289 ◽  
Author(s):  
M. Clayman ◽  
D. Tsang ◽  
A. F. De Nicola ◽  
R. M. Johnstone

The inhibition of ascorbate transport by rat adrenal quarters in response to steroidogenesis in vitro was shown to be highly specific with respect to tissue, substrate and steroidogenic agent. The transport system in vitro is capable of net accumulation of ascorbate. The evidence is consistent with the conclusion that ascorbate `depletion' in the adrenal gland is due to a specific block by corticoids of the uptake of ascorbate.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 134-135
Author(s):  
Jennifer A Hernandez Gifford ◽  
Emily Ferranti ◽  
Kylee Forrest ◽  
Craig A Gifford

Abstract Female fertility is dependent on estradiol concentrations which regulate a multitude of ovarian functions including follicle development and oocyte maturation leading to ovulation of a viable oocyte. Estradiol biosynthesis is regulated by coordinated actions of follicle-stimulating hormone and intra-ovarian control mechanisms including the co-transcription factor beta-catenin. Beta-catenin is a multi-faceted protein recognized for its role in granulosa cell steroid production and is shown to be modulated by lipopolysaccharide (LPS), the endotoxin responsible for stimulation of the immune system in infections caused by Gram-negative bacteria. Beef heifers treated with subacute concentrations of LPS during a synchronized follicular wave demonstrate a decline in serum estradiol concentrations 50 h after CIDR withdrawal, corresponding with dominant follicle maturation and preceding ovulation. The endotoxin exposure also resulted in increased LPS concentration and E2:P4 ratios in follicular fluid suggesting that low dose LPS modulates the intra-follicular hormonal milieu. Additionally, in a granulosa cell line, LPS treatment decreased mRNA expression of aromatase and beta-catenin. These data indicate that LPS alters E2 synthesis by modulating beta-catenin and subsequent steroidogenic enzyme expression. To further explore the contribution of naturally occurring LPS exposure on follicular steroid production and developing oocytes, bovine ovary pairs were collected from local abattoirs. Oocytes were aspirated from small follicles and matured in vitro to evaluate meiotic events related to nuclear maturation and spindle morphology. Small follicles from ovarian pairs were separated by the detectable LPS concentrations into high and low LPS groups. Oocytes matured from low LPS follicles demonstrated an increase in the percent of abnormal maturation events. Data indicate that induced or naturally occurring low doses of LPS can alter circulating and follicular estradiol concentrations impairing oocyte maturation. Perturbation to local ovarian signaling cascades from subclinical inflammatory disease may be an unappreciated factor altering fertility and leading to decreased cow retention.


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