THE EFFECT OF PIG PITUITARY ACTH FRACTIONS ON DIFFERENT PARAMETERS OF ADRENOCORTICAL ACTIVITY

1963 ◽  
Vol 41 (6) ◽  
pp. 1455-1467 ◽  
Author(s):  
E. de Jager ◽  
J. D. H. Homan ◽  
D. de Wied
Keyword(s):  
Plasma Corticosterone ◽  
Buffer System ◽  
Adrenocortical Activity ◽  
In Vivo Assays ◽  
In Vitro Technique ◽  
Separate Fraction ◽  
Hypophysectomized Rats ◽  
Assay Methods

Purified unhydrolyzed corticotrophin was separated into five fractions by chromatography on a column of carboxymethyl cellulose, using pyridine – acetic acid as a buffer system. These fractions were biologically assayed by means of the in vitro technique of Saffran and Schally, the adrenal ascorbic acid depletion test of Sayers et al., and an assay based on the increase of plasma corticosterone levels in hypophysectomized rats. In the in vivo assays both the intravenous and subcutaneous routes of injection were applied.The principal aim of this study was to investigate for each separate fraction the extent to which the potencies according to the Sayers test correspond with the potencies obtained by the plasma corticosterone method. When comparing results found after identical routes of injection, a fair agreement was observed for those fractions showing electrophoretic relationship and together accounting for the major part of the biological activity of the starting material. However, the minor fractions showed significant differences.These findings are discussed together with the results of the classical assay methods and their deviations from data reported in the literature.

THE EFFECT OF PIG PITUITARY ACTH FRACTIONS ON DIFFERENT PARAMETERS OF ADRENOCORTICAL ACTIVITY

1963 ◽  
Vol 41 (1) ◽  
pp. 1455-1467
Author(s):  
E. de Jager ◽  
J. D. H. Homan ◽  
D. de Wied
Keyword(s):  
Plasma Corticosterone ◽  
Buffer System ◽  
Adrenocortical Activity ◽  
In Vivo Assays ◽  
In Vitro Technique ◽  
Separate Fraction ◽  
Hypophysectomized Rats ◽  
Assay Methods

Purified unhydrolyzed corticotrophin was separated into five fractions by chromatography on a column of carboxymethyl cellulose, using pyridine – acetic acid as a buffer system. These fractions were biologically assayed by means of the in vitro technique of Saffran and Schally, the adrenal ascorbic acid depletion test of Sayers et al., and an assay based on the increase of plasma corticosterone levels in hypophysectomized rats. In the in vivo assays both the intravenous and subcutaneous routes of injection were applied.The principal aim of this study was to investigate for each separate fraction the extent to which the potencies according to the Sayers test correspond with the potencies obtained by the plasma corticosterone method. When comparing results found after identical routes of injection, a fair agreement was observed for those fractions showing electrophoretic relationship and together accounting for the major part of the biological activity of the starting material. However, the minor fractions showed significant differences.These findings are discussed together with the results of the classical assay methods and their deviations from data reported in the literature.

Adrenocorticotropic activity in the rat assessed by in vivo and in vitro indices

1963 ◽  
Vol 205 (6) ◽  
pp. 1083-1088 ◽  
Author(s):  
J. J. Van Goch ◽  
D. De Wied ◽  
E. Schönbaum
Keyword(s):  
Ascorbic Acid ◽  
Plasma Corticosterone ◽  
In Vitro Technique ◽  
Rat Adrenals ◽  
Hypophysectomized Rats ◽  
Adrenal Corticosterone ◽  
Intact Rats

Several indices of adrenocorticotropic (ACTH) activity were compared in order to establish the index most suitable for assay purposes, particularly of ACTH in blood. In hypophysectomized rats, the effects of ACTH on adrenal ascorbic acid, cholesterol, and steroid formation in vitro were studied. In intact rats, the effects of formalin on these variables as well as on the adrenal and plasma corticosterone levels and hypophyseal and blood ACTH activity were measured. Adrenal corticosterone as well as steroid formation in vitro increased very rapidly after stimulation by ACTH. In hypophysectomized rats, after intravenous ACTH, significant increases were observed after 5 min. In normal rats, 3 min after the injection of formalin, significant increases of steroid formation in vitro and ACTH activity were observed. The in vitro technique is suitable for the study of changes in ACTH activity. ACTH increases the fraction of corticosterone found in the total amount of corticoid secreted by rat adrenals in vitro.

Cytotoxic and Chemopreventive Effects of Gemin D Against Different Mutagens Using In Vitro and In Vivo Assays

2017 ◽  
Vol 17 (5) ◽  
pp. 712-718 ◽  
Author(s):  
Cristiene Costa Carneiro ◽  
Aroldo Vieira de Moraes-Filho ◽  
Amanda Silva Fernandes ◽  
Suzana da Costa Santos ◽  
Daniela de Melo e Silva ◽  
...  
Keyword(s):  
In Vivo Assays

scholarly journals Cork Oak Endophytic Fungi as Potential Biocontrol Agents against Biscogniauxia mediterranea and Diplodia corticola

2020 ◽  
Vol 6 (4) ◽  
pp. 287
Author(s):  
Daniela Costa ◽  
Rui M. Tavares ◽  
Paula Baptista ◽  
Teresa Lino-Neto
Keyword(s):  
Fungal Endophytes ◽  
Cork Oak ◽  
In Vivo Assays ◽  
Oak Trees ◽  
Treatment Measures ◽  
Dual Plate ◽  
Antagonistic Potential ◽  
Selection Of

An increase in cork oak diseases caused by Biscogniauxia mediterranea and Diplodia corticola has been reported in the last decade. Due to the high socio-economic and ecologic importance of this plant species in the Mediterranean Basin, the search for preventive or treatment measures to control these diseases is an urgent need. Fungal endophytes were recovered from cork oak trees with different disease severity levels, using culture-dependent methods. The results showed a higher number of potential pathogens than beneficial fungi such as cork oak endophytes, even in healthy plants. The antagonist potential of a selection of eight cork oak fungal endophytes was tested against B. mediterranea and D. corticola by dual-plate assays. The tested endophytes were more efficient in inhibiting D. corticola than B. mediterranea growth, but Simplicillium aogashimaense, Fimetariella rabenhorstii, Chaetomium sp. and Alternaria alternata revealed a high potential to inhibit the growth of both. Simplicillium aogashimaense caused macroscopic and microscopic mycelial/hyphal deformations and presented promising results in controlling both phytopathogens’ growth in vitro. The evaluation of the antagonistic potential of non-volatile and volatile compounds also revealed that A. alternata compounds could be further explored for inhibiting both pathogens. These findings provide valuable knowledge that can be further explored in in vivo assays to find a suitable biocontrol agent for these cork oak diseases.

Reduced and S-carboxymethylated human growth hormone: a probe for diabetogenic action

1984 ◽  
Vol 247 (5) ◽  
pp. E639-E644
Author(s):  
C. M. Cameron ◽  
J. L. Kostyo ◽  
J. A. Rillema ◽  
S. E. Gennick
Keyword(s):  
Growth Hormone ◽  
Amino Acid ◽  
Human Growth Hormone ◽  
Human Growth ◽  
Mouse Mammary Gland ◽  
Amino Acid Incorporation ◽  
Acid Incorporation ◽  
Hypophysectomized Rats

The biological activity profile of reduced and S-carboxymethylated human growth hormone (RCM-hGH) was determined to establish its suitability for study of the diabetogenic property of hGH. RCM-hGH was found to have greatly attenuated in vivo growth-promoting activity in the 9-day weight-gain test in hypophysectomized rats (approximately 1%) and to have a similar low order of in vitro activity in stimulating amino acid incorporation into the protein of the isolated rat diaphragm. RCM-hGH also only had approximately 1% of the in vitro insulin-like activity of the native hormone on isolated adipose tissue from hypophysectomized rats. In contrast, RCM-hGH retained substantial in vivo diabetogenic activity in the ob/ob mouse, appearing to have approximately 50% of the activity of the native hormone. RCM-hGH was also found to retain significant, although attenuated (25%), in vitro lactogenic activity when tested for the ability to stimulate amino acid incorporation into a casein-rich protein fraction in mouse mammary gland explants. Because RCM-hGH exhibits a high degree of diabetogenic activity, although lacking significant anabolic or insulin-like activities, it will be useful as a "monovalent" probe for the study of the molecular mechanism of the diabetogenic action of GH.

scholarly journals Let-7a regulates EV secretion and mitochondrial oxidative phosphorylation by targeting SNAP23 in colorectal cancer

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
You Dong Liu ◽  
Xiao Peng Zhuang ◽  
Dong Lan Cai ◽  
Can Cao ◽  
Qi Sheng Gu ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
Metabolic Reprogramming ◽  
Luciferase Reporter ◽  
Mitochondrial Oxidative Phosphorylation ◽  
In Vivo Assays ◽  
Reporter Assays ◽  
Extracellular Mirna

Abstract Background MicroRNAs (miRNAs) are abundant in tumor-derived extracellular vesicles (EVs) and the functions of extracellular miRNA to recipient cells have been extensively studied with tumorigenesis. However, the role of miRNA in EV secretion from cancer cells remains unknown. Methods qPCR and bioinformatics analysis were applied for determining extracellular let-7a expression from CRC patient serum and cells. Nanosight particle tracking analysis was performed for investigating the effect of let-7a on EV secretion. Luciferase reporter assays was used for identifying targeted genes synaptosome-associated protein 23 (SNAP23). In vitro and in vivo assays were used for exploring the function of let-7a/SNAP23 axis in CRC progression. Bioenergetic assays were performed for investigating the role of let-7a/SNAP23 in cellular metabolic reprogramming. Results let-7a miRNA was elevated in serum EVs from CRC patients and was enriched in CRC cell-derived EVs. We determined that let-7a could suppress EV secretion directly targeting SNAP23. In turn, SNAP23 promotes EV secretion of let-7a to downregulate the intracellular let-7a expression. In addition, we found a novel mechanism of let-7a/SNAP23 axis by regulating mitochondrial oxidative phosphorylation (OXPHOS) through Lin28a/SDHA signaling pathway. Conclusions Let-7a plays an essential role in not only inhibiting EV secretion, but also suppressing OXPHOS through SNAP23, resulting in the suppression of CRC progression, suggesting that let-7a/SNAP23 axis could provide not only effective tumor biomarkers but also novel targets for tumor therapeutic strategies.

Adrenocortical function in aging exercise-trained rats

1977 ◽  
Vol 43 (5) ◽  
pp. 839-843 ◽  
Author(s):  
J. A. Severson ◽  
R. D. Fell ◽  
J. G. Tuig ◽  
D. R. Griffith
Keyword(s):  
Age Groups ◽  
Plasma Corticosterone ◽  
Treadmill Running ◽  
Adrenocortical Function ◽  
Elevated Plasma ◽  
Corticosterone Concentration ◽  
Relationship Of ◽  
The Relationship

Plasma corticosterone concentrations and in vitro adrenal secretion of corticosterone were determined in exercise-trained rats. Rats, 100, 200, and 300 days of age, were trained for a 10-wk period by treadmill running. Following the training program, rats were subjected to an acute bout of swimming. Acute swimming elevated plasma corticosterone concentrations in all age groups. At 170 days of age, the plasma corticosterone concentration following swimming was higher in exercise-trained rats than in controls. The opposite was true of acutely swum rats at 270 and 370 days of age. Acute swimming elevated the in vitro adrenal gland response to adrenocorticotropic hormone stimulation in control rats at all ages and in trained rats at 170 days of age. The in vivo relationship of epinephrine and the pituitary adrenal system is suggested as a mechanism which could have caused this response. The relationship of secretion rates to plasma corticosterone concentrations indicated that extra-adrenal mechanisms, such as decreased turnover, were also responsible for the elevated plasma corticosterone levels observed in response to acute swimming.

Correlation between in vitro and in vivo assays in selection of probiotics from traditional species of bacteria

2017 ◽  
Vol 68 ◽  
pp. 83-90 ◽  
Author(s):  
Gabriel Vinderola ◽  
Miguel Gueimonde ◽  
Carlos Gomez-Gallego ◽  
Lucrecia Delfederico ◽  
Seppo Salminen
Keyword(s):  
In Vivo Assays ◽  
Selection Of
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