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.

IN VITRO INHIBITION OF UDP GLUCURONOSYLTRANSFERASES BY ATAZANAVIR AND OTHER HIV PROTEASE INHIBITORS AND THE RELATIONSHIP OF THIS PROPERTY TO IN VIVO BILIRUBIN GLUCURONIDATION

2005 ◽  
Vol 33 (11) ◽  
pp. 1729-1739 ◽  
Author(s):  
Donglu Zhang ◽  
Theodore J. Chando ◽  
Donald W. Everett ◽  
Christopher J. Patten ◽  
Shangara S. Dehal ◽  
...  
Keyword(s):  
Protease Inhibitors ◽  
Hiv Protease ◽  
Hiv Protease Inhibitors ◽  
In Vitro Inhibition ◽  
Relationship Of ◽  
The Relationship

scholarly journals SIMILARITY OF THE KINETICS OF INVERTASE ACTION IN VIVO AND IN VITRO. III

1933 ◽  
Vol 16 (4) ◽  
pp. 571-577 ◽  
Author(s):  
J. M. Nelson ◽  
B. G. Wilkes
Keyword(s):  
Physiological Activity ◽  
Water Concentration ◽  
Invertase Activity ◽  
Yeast Cells ◽  
Identical Manner ◽  
A Cell ◽  
Relationship Of ◽  
The Relationship

1. The relationship of sucrose and water concentration to invertase activity in vivo and in vitro has been studied under the same environmental conditions. 2. The sucroclastic activity of S. cerevisiae cells and of invertase solutions prepared from them reacts to changes in sucrose and water concentration in an identical manner. 3. The invertase contained in living yeast cells is just as freely exposed to the conditions of sucrose and water concentrations of the suspending medium as it would be if it were contained in a cell-free solution. Weight is added to the previous suggestion (2) that yeast invertase exerts its physiological activity in a region quite close to the surface of the cell.

Hematopoietic-repopulating defects from STAT5-deficient bone marrow are not fully accounted for by loss of thrombopoietin responsiveness

Blood ◽  
2004 ◽  
Vol 103 (8) ◽  
pp. 2965-2972 ◽  
Author(s):  
Heath L. Bradley ◽  
Christine Couldrey ◽  
Kevin D. Bunting
Keyword(s):  
Bone Marrow ◽  
Hematopoietic Stem ◽  
Fold Reduction ◽  
Thrombopoietin Receptor ◽  
Direct Head ◽  
Relationship Of ◽  
The Relationship

Abstract Signal transducer and activator of transcription-5 (STAT5) plays an important role in repopulating activity of hematopoietic stem cells (HSCs). However, the relationship of STAT5 activation with early acting cytokine receptors is not well established. We have directly compared bone marrow (BM) from mice mutant for STAT5a and STAT5b (STAT5ab-/-) with that from mice lacking c-Mpl (c-Mpl-/-), the thrombopoietin receptor. Both STAT5 and c-Mpl deficiency only mildly affected committed myeloid progenitors assayed in vitro, but STAT5ab-/- BM showed lower Gr-1+ (4.4-fold), B220+ (23-fold), CD4+ (20-fold), and Ter119+ (17-fold) peripheral blood repopulating activity than c-Mpl-/- BM against wild-type competitor in long-term repopulating assays in vivo. Direct head-to-head competitions of STAT5ab-/- BM and c-Mpl-/- BM showed up to a 25-fold reduction in STAT5ab-/- contribution. Differences affecting reconstitution of primitive c-Kit+Lin-Sca-1+ multipotent progenitor (MPP)/HSC (1.8-fold) and c-Kit+Lin-Sca-1- oligopotent progenitor BM fractions (3.3-fold) were more modest. In serial transplantation experiments, STAT5ab-/- and c-Mpl-/- BM both failed to provide consistent engraftment in tertiary hosts and could not radioprotect lethally irradiated quaternary recipients. These results indicate substantial overlap in c-Mpl-STAT5 signaling defects at the MPP/HSC level but indicate that STAT5 is activated independent of c-Mpl to promote multilineage hematopoietic differentiation. (Blood. 2004;103:2965-2972)

scholarly journals Deoxyribonucleic acid synthesis in mammalian nuclei. Incorporation of deoxyribonucleotides and chain-terminating nucleotide analogues

1971 ◽  
Vol 121 (5) ◽  
pp. 803-809 ◽  
Author(s):  
M. A. Waqar ◽  
L. A. Burgoyne ◽  
M. R. Atkinson
Keyword(s):  
Dna Synthesis ◽  
Deoxyribonucleic Acid ◽  
Acid Synthesis ◽  
Deoxyribonucleic Acid Synthesis ◽  
Dna Chain ◽  
Relationship Of ◽  
The Relationship ◽  
Neighbour Analysis

The properties of a nuclear preparation from rat liver and thymus are described. (1) Nearest-neighbour analysis after incorporation of 32P-labelled nucleotide residues from dATP, dCTP, dGTP, dTTP and arabinofuranosyl analogues of CTP and ATP shows template-dependent DNA synthesis. (2) Where primer termini are limiting, incorporation of arabinofuranosyl analogues of AMP and CMP residues proceeds to a limit indicating that both of these analogues are DNA chain terminators. (3) No large differences have been found between the priming potentialities or the intrinsic DNA polymerase activities of nuclei from resting or regenerating liver and the relationship of this DNA synthesis in vitro to DNA replication or repair in vivo is briefly discussed.

scholarly journals Oxytocin Controls Chondrogenesis and Correlates with Osteoarthritis

2020 ◽  
Vol 21 (11) ◽  
pp. 3966
Author(s):  
Christian H. Roux ◽  
Didier F. Pisani ◽  
Pierre Gillet ◽  
Eric Fontas ◽  
Hédi Ben Yahia ◽  
...  
Keyword(s):  
Matrix Protein ◽  
Adipose Derived Stem Cells ◽  
Mrna Transcript ◽  
X Ray ◽  
Relationship Of ◽  
The Relationship ◽  
Immunohistochemical Analyses ◽  
Lesion Severity

This study investigated the relationship of oxytocin (OT) to chondrogenesis and osteoarthritis (OA). Human bone marrow and multipotent adipose-derived stem cells were cultured in vitro in the absence or presence of OT and assayed for mRNA transcript expression along with histological and immunohistochemical analyses. To study the effects of OT in OA in vivo, a rat model and a human cohort of 63 men and 19 women with hand OA and healthy controls, respectively, were used. The baseline circulating OT, interleukin-6, leptin, and oestradiol levels were measured, and hand X-ray examinations were performed for each subject. OT induced increased aggrecan, collagen (Col) X, and cartilage oligomeric matrix protein mRNA transcript levels in vitro, and the immunolabelling experiments revealed a normalization of Sox9 and Col II protein expression levels. No histological differences in lesion severity were observed between rat OA groups. In the clinical study, a multivariate analysis adjusted for age, body mass index, and leptin levels revealed a significant association between OA and lower levels of OT (odds ratio = 0.77; p = 0.012). Serum OT levels are reduced in patients with hand OA, and OT showed a stimulatory effect on chondrogenesis. Thus, OT may contribute to the pathophysiology of OA.

EFFECTS OF ACTH AND ITS O-NITROPHENYL SULPHENYL DERIVATIVE ON ADRENOCORTICAL FUNCTION IN VIVO

1976 ◽  
Vol 82 (3) ◽  
pp. 587-599 ◽  
Author(s):  
J. Ramachandran ◽  
Y. C. Kong ◽  
Susanna Liles
Keyword(s):  
Cyclic Amp ◽  
Adrenal Weight ◽  
Adrenocortical Function ◽  
Tryptophan Residue ◽  
Adult Rats ◽  
Corticosterone Concentration ◽  
Hypophysectomized Rats ◽  
Stimulation Of

ABSTRACT Both ACTH and NPS-ACTH in which the single tryptophan residue of the hormone is modified were able to stimulate adrenal corticosterone concentration to the same extent in hypophysectomized rats, although a higher dose of NPS-ACTH was required. ACTH stimulated adrenal cyclic AMP levels 120-fold in hypophysectomized rats whereas NPS-ACTH caused a marginal increase. In the case of ACTH, low doses of the hormone capable of producing maximal stimulation of corticosterone synthesis did not produce any detectable change in cyclic AMP concentration. The rates of secretion of corticosterone induced by ACTH and NPS-ACTH in vivo were the same. NPS-ACTH was found to be 1.2% as potent as ACTH. The role of cyclic AMP in adrenal repair was investigated by administering equipotent doses of ACTH or NPS-ACTH to hypophysectomized rats. In adult rats both failed to produce a significant increase in adrenal weight. Adrenal function (measured by responsiveness to exogenous ACTH in vitro) was restored by NPS-ACTH but not to the same degree as ACTH. In hypophysectomized weanling rats, ACTH produced a small but significant increase in adrenal weight but NPS-ACTH did not. These results suggest that an increase in adrenal cyclic AMP may not be obligatory for the stimulation of steroidogenesis by ACTH and that some of the trophic actions of the hormone may be mediated by cyclic AMP.

scholarly journals Comparison of the survival on ice of thawed Theileria parva sporozoites of different stocks cryoprotected by glycerol or sucrose

2007 ◽  
Vol 74 (1) ◽  
Author(s):  
V. Mbao ◽  
D. Berkvens ◽  
P. Dorny ◽  
P. Van Den Bossche ◽  
T. Marcotty
Keyword(s):  
Effective Dose ◽  
East Coast ◽  
Theileria Parva ◽  
In Vitro Techniques ◽  
Protection Rate ◽  
Method Of Assessment ◽  
Relationship Of ◽  
The Relationship

Stabilates of Theileria parva sporozoites are mostly delivered in liquid nitrogen tanks to the East Coast fever immunization points. Using an in vitro titration model, we assessed the loss of infectivity of several stabilates when they are stored in ice baths for up to 24 h. Comparisons, with respect to rates of loss of infectivity, were made between T. parva stocks (Chitongo and Katete), cryoprotectants (sucrose and glycerol) and method of assessment (in vivo and in vitro techniques). Chitongo and Katete stabilates showed similar loss dynamics. The losses were 1-4 % (depending on parasite stock) and 3 % per hour of storage for glycerol and sucrose stabilates respectively, and the loss rates were not significantly different. The results suggest that Chitongo stabilates and sucrose cryoprotected suspensions can be delivered on ice as is done for Katete. A graphical relationship of in vitro effective dose at 50 % infectivity (ED50) and in vivo protection rate was made. The relationship showed a 35 % loss of protection for a relatively low corresponding increase of ED50 from 0.006 to 0.007 tick equivalent.

Sign in / Sign up

Export Citation Format

Share Document