ADRENOCORTICAL RESPONSE UPON REPEATED STIMULATION WITH CORTICOTROPHIN IN PATIENTS LACKING ENDOGENOUS CORTICOTROPHIN SECRETION

1977 ◽  
Vol 85 (3) ◽  
pp. 595-607 ◽  
Author(s):  
J. Kolanowski ◽  
W. Esselinckx ◽  
C. Nagant de Deuxchaisnes ◽  
J. Crabbé
Keyword(s):  
Urinary Excretion ◽  
Plasma Cortisol ◽  
Secretory Activity ◽  
Adrenocortical Function ◽  
Steroid Withdrawal ◽  
Short Term ◽  
Acth Stimulation ◽  
Control Subjects ◽  
Adrenocortical Response

ABSTRACT The role played by a normal endogenous corticotrophin secretion in the mechanism by which adrenocortical steroidogenic response to ACTH increases as a result of previous administration of the peptide, was assessed by repeated ACTH administration in 25 patients under prolonged cortico-therapy and in 13 patients with anterior hypophyseal insufficiency. The response to ACTH (250 μg tetracosapeptide iv over 8 h) was evaluated on the basis of changes in plasma cortisol and in the urinary excretion of cortisol and 17-ketogenic steroids. The steroidogenic response to the first ACTH infusion was markedly reduced in these patients when compared to control subjects, or even to subjects on short-term dexametasone. However, in these patients as in normals, acute ACTH administration was followed by a phase, lasting for 3 days at least, during which the steroidogenic response to further ACTH stimulation was increased. When ACTH was infused repeatedly on 4 consecutive days in patients on long-term cortico-therapy, adrenocortical responsiveness was rapidly restored to normal. By contrast, when ACTH was administered every fourth day, a less pronounced enhancement of adrenocortical responsiveness occurred, the secretory activity returning to previous hypo-adrenal state between each stimulation.. These data indicate that the mechanism of amplified adrenocortical response to ACTH does not require continuous endogenous corticotrophin secretion. They further suggest that intermittent corticotrophin therapy may be more adequate in promoting recovery of adrenocortical function on steroid withdrawal than a schedule consisting of daily ACTH administration, since the latter is thought to slow down hypothalamic-pituitary activity because of concomitant sustained enhancement of steroidogenesis.

scholarly journals Energetics of stress: linking plasma cortisol levels to metabolic rate in mammals

2016 ◽  
Vol 12 (1) ◽  
pp. 20150867 ◽  
Author(s):  
Catherine G. Haase ◽  
Andrea K. Long ◽  
James F. Gillooly
Keyword(s):  
Metabolic Rate ◽  
Plasma Cortisol ◽  
Physiological Stress ◽  
Stress Hormone ◽  
Short Term ◽  
Primary Stress ◽  
Baseline Concentrations ◽  
Species Comparisons ◽  
Point Of Departure

Physiological stress may result in short-term benefits to organismal performance, but also long-term costs to health or longevity. Yet, we lack an understanding of the variation in stress hormone levels (i.e. glucocorticoids) that exist within and across species. Here, we present comparative analyses that link the primary stress hormone in most mammals (i.e. cortisol) to metabolic rate. We show that baseline concentrations of plasma cortisol vary with mass-specific metabolic rate among cortisol-dominant mammals, and both baseline and elevated concentrations scale predictably with body mass. The results quantitatively link a classical measure of physiological stress to whole-organism energetics, providing a point of departure for cross-species comparisons of stress levels among mammals.

Metabolism of cortisol in anorexia nervosa

1990 ◽  
Vol 122 (6) ◽  
pp. 753-758 ◽  
Author(s):  
H. Vierhapper ◽  
A. Kiss ◽  
P. Nowotny ◽  
S. Wiesnagrotzki ◽  
C. Monder ◽  
...  
Keyword(s):  
Anorexia Nervosa ◽  
Urinary Excretion ◽  
Plasma Concentrations ◽  
Adrenocortical Function ◽  
Acth Stimulation ◽  
Healthy Women ◽  
Rate Limiting Step ◽  
Enhanced Secretion ◽  
Excretion Rates ◽  
Steroid Excretion

Abstract. In patients with anorexia nervosa 24-h mean plasma concentration of cortisol were 0.44± 0.09 μmol/l (normal < 0.28 μmol/l). Following stimulation by ACTH (1–24) urinary excretion rates of cortisol were stimulated from 0.22 ± 0.08 to 4.85 ± 2.78 μmol/24 h. Similarly, plasma concentrations of the glucocorticoid metabolite, tetrahydrocortisone, increased from 23.3 ± 9.0 to 47.3 ± 30.2 nmol/l; urinary excretion rates of tetrahydrocortisone increased from 3.61 ± 0.90 to 8.40 ± 1.72 μmol/24 h. The relative share of the sulphate, glucuronide and free fractions of tetrahydrocortisone in the patients' urine did not indicate any defect in metabolization of this steroid metabolite. Excretion rates of the four glucocorticoid tetrahydro-metabolites, tetrahydrocortisone, allotetrahydrocortisone, tetrahydrocortisol, and allo-tetrahydrocortisol, expressed as percent of total steroid excretion, were similar in patients with anorexia and in healthy women under basal conditions (24 ± 6 vs 23 ± 6%) and during stimulation by ACTH (1–24) (36 ± 10 vs 45 ± 6%). The share of the two androgen metabolites, androsterone and etiocholanolone, was 24 ± 5% of total steroid excretion (basal; healthy women: 27 ± 8%) and 13 ± 2% (ACTH stimulation; healthy women: 12 ± 4%) in patients with anorexia nervosa. Thus, analysis of urinary steroid excretion rates did not indicate a shift in adrenocortical function. The results confirmed enhanced secretion of cortisol in patients with anorexia nervosa under basal conditions and during/following stimulation by ACTH. The ACTH-induced increase in the concentrations of the tetrahydro-glucocorticoid metabolites in urine was less pronounced than that of cortisol. The data strongly suggest a rate-limiting step in the transformation of cortisol into its main metabolites, most likely an impaired reduction of the double bond in positions C4/C5.

Serum clearance and urinary excretion of folic acid in milk-fed and weaned calves

1997 ◽  
Vol 77 (1) ◽  
pp. 69-75 ◽  
Author(s):  
C. L. Girard ◽  
J. J. Matte
Keyword(s):  
Folic Acid ◽  
Urinary Excretion ◽  
Folic Acid Supplementation ◽  
Short Term ◽  
Folate Status ◽  
Serum Clearance ◽  
Key Words Folic Acid ◽  
Erythrocyte Concentration ◽  
Milk Replacers

Thirty male calves were assigned to treatments in a 2 × 3 factorial experiment in which the diet (exclusively milk replacers or dry feed) and the duration of the period of folic acid supplementation (no, short-term, i.e., 7 d before each period of evaluation of the folate status, or long-term supplementation, i.e., throughout the experiment) were the two main factors. During their first 4 mo of life, the folate status of calves was evaluated monthly. In milk-fed calves, erythrocyte concentration of folates increased with the duration of the supplementation (P = 0.008) but it decreased with age (P = 0.01). In weaned calves, it was similar for calves receiving no or a short-term supplementation but it was higher for those receiving the long-term supplementation and the decrease with age was more marked with this last treatment (supplementation × age, P = 0.01). Serum clearance of an i.v. bolus of folic acid was similar for milk-fed and weaned calves (P = 0.2), it was more rapid with age (P = 0.02), but it slowed down with the duration of the supplementation (P = 0.05). The percentage of the dose of folic acid injected i.m. recovered in urine was higher in milk-fed than in weaned calves (P = 0.0001) and it decreased with age (P = 0.0001). The present results suggest that the tissue demand for folic acid is high in preruminant and ruminant calves and it increases during the first 4 mo of life. Key words: Folic acid, serum clearance, urinary excretion, milk-fed calf, weaned calf

Restoration of Thiamine Status with White or Whole Wheat Bread in a Thiamine-Depleted Rat Model

2007 ◽  
Vol 77 (1) ◽  
pp. 46-56
Author(s):  
Batifoulier ◽  
Verny ◽  
Besson ◽  
Chanliaud ◽  
Rémésy ◽  
...  
Keyword(s):  
Urinary Excretion ◽  
Rat Model ◽  
Wheat Bread ◽  
White Bread ◽  
Thiamine Diphosphate ◽  
Short Term ◽  
Initial Values ◽  
Whole Wheat ◽  
Whole Wheat Bread

Long-term thiamine deficiency has been largely documented, whilst little is known about effects of short-term depletion/repletion periods on thiamine vitamers status. Rats were submitted to short-term depletion (8 days) followed by different durations of repletion (3 or 14 days) with thiamine from bread (whole wheat bread or white bread, whole B and white B respectively) or corresponding controls. Short-term depletion drastically decreased plasma thiamine (–97%) and its urinary excretion (–77%). TDP (thiamine diphosphate) was strongly affected in liver (–67%) but less affected in cerebellum (–38%) or kidneys (–45%). Short-term repletion (3 days) with whole B diet or its control restored TDP at initial values in cerebellum and kidneys. A longer repletion (14 days) was required to restore liver TDP. Comparison of the diet groups indicates that thiamine status in tissues of rat fed whole B or white B diet was comparable to that of rats fed purified thiamine. Plasma thiamine concentration could not be restored at initial values in the bread groups or respective controls. In conclusion, thiamine in whole wheat bread appears effective in preventing marginal deficiencies and plasma thiamine is a less reliable indicator of thiamine status than tissue TDP levels.

LACK OF EFFECT OF DEXAMETHASONE ON THE ADRENOCORTICAL RESPONSE TO CORTICOTROPHIN IN SHEEP WITH ADRENAL AUTOTRANSPLANTS

1969 ◽  
Vol 43 (2) ◽  
pp. 191-196
Author(s):  
D. S. HART ◽  
D. W. BEAVEN ◽  
N. C. FRANCE ◽  
E. A. ESPINER
Keyword(s):  
Adrenal Cortex ◽  
Direct Effect ◽  
Cortisol Secretion ◽  
Short Term ◽  
Acth Stimulation ◽  
Physiological Conditions ◽  
Adrenocortical Response ◽  
Term Administration ◽  
Adrenal Response ◽  
Significant Change

SUMMARY Sheep with adrenal autotransplants were used to study the direct effect of dexamethasone on the adrenal response to corticotrophin (ACTH). When the adrenal cortex, under constant ACTH stimulation, was infused with dexamethasone at rates from 9·5 to 41 μg./min., no significant change in cortisol secretion occurred. Since concentrations of dexamethasone as high as 2 to 4 μg./ml. of infusing blood were maintained for up to 70 min., it is concluded that short-term administration of dexamethasone has no important effect on the adrenal sensitivity to ACTH in sheep under physiological conditions.

scholarly journals Sensory Integration and Standing Balance in Adolescent Taekwondo Practitioners

2012 ◽  
Vol 24 (1) ◽  
pp. 142-151 ◽  
Author(s):  
Shirley S.M. Fong ◽  
Gabriel Y.F. Ng
Keyword(s):  
Sensory System ◽  
Testing System ◽  
Balance Performance ◽  
Short Term ◽  
Control Subjects ◽  
Balance Testing ◽  
Significant Difference ◽  
Short And Long Term ◽  
Different Levels

Taekwondo (TKD) is a popular sport among adolescents. This study aims to (a) compare the balance performance between adolescent TKD practitioners at different levels of expertise with nonpractitioners and (b) determine the sensory system(s) that contributed to the balance function in adolescents with and without TKD training. Subjects with >5 years of TKD training (n = 11), <4 years of training (n = 10), and no training (n = 10) participated in this study. The sway velocity, somatosensory, vestibular and visual ratios were recorded during standing on a balance testing system. Both short- and long-term TKD practitioners swayed slower than control subjects when standing on one leg (p = .016 and 0.012, respectively). However, only short-term practitioners have better visual ratio (p = .018) and vestibular ratio (p = .029) than control subjects. There was no significant difference in the somatosensory ratio among the 3 groups. We conclude that adolescents undertaking TKD training may have better balance performance than untrained subjects.

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Comparison of Auditory, Language, Memory, and Attention Abilities in Children With and Without Listening Difficulties

2020 ◽  
Vol 29 (4) ◽  
pp. 710-727
Author(s):  
Beula M. Magimairaj ◽  
Naveen K. Nagaraj ◽  
Alexander V. Sergeev ◽  
Natalie J. Benafield
Keyword(s):  
Auditory Processing ◽  
Short Term Memory ◽  
Group Differences ◽  
Long Term Memory ◽  
Short Term ◽  
Significant Group ◽  
Term Memory ◽  
Memory And Attention ◽  
Speed And Accuracy

Objectives School-age children with and without parent-reported listening difficulties (LiD) were compared on auditory processing, language, memory, and attention abilities. The objective was to extend what is known so far in the literature about children with LiD by using multiple measures and selective novel measures across the above areas. Design Twenty-six children who were reported by their parents as having LiD and 26 age-matched typically developing children completed clinical tests of auditory processing and multiple measures of language, attention, and memory. All children had normal-range pure-tone hearing thresholds bilaterally. Group differences were examined. Results In addition to significantly poorer speech-perception-in-noise scores, children with LiD had reduced speed and accuracy of word retrieval from long-term memory, poorer short-term memory, sentence recall, and inferencing ability. Statistically significant group differences were of moderate effect size; however, standard test scores of children with LiD were not clinically poor. No statistically significant group differences were observed in attention, working memory capacity, vocabulary, and nonverbal IQ. Conclusions Mild signal-to-noise ratio loss, as reflected by the group mean of children with LiD, supported the children's functional listening problems. In addition, children's relative weakness in select areas of language performance, short-term memory, and long-term memory lexical retrieval speed and accuracy added to previous research on evidence-based areas that need to be evaluated in children with LiD who almost always have heterogenous profiles. Importantly, the functional difficulties faced by children with LiD in relation to their test results indicated, to some extent, that commonly used assessments may not be adequately capturing the children's listening challenges. Supplemental Material https://doi.org/10.23641/asha.12808607

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