scholarly journals Endocrine and Electrolyte Balances during Periovulatory Period in Cycling Mares

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 520 ◽  
Author(s):  
Katiuska Satué ◽  
Esterina Fazio ◽  
Ana Muñoz ◽  
Pietro Medica
Keyword(s):  
Estrous Cycle ◽  
Hpa Axis ◽  
Adrenocorticotropic Hormone ◽  
Venous Blood ◽  
Competitive Elisa ◽  
Direct Relation ◽  
Plasma Acth ◽  
Blood Samples ◽  
Hypothalamic Pituitary Adrenal ◽  
Stimulation Of

In cycling females, the periovulatory period is characterized by stimulation of the hypothalamic pituitary adrenal (HPA) axis. The aim of present study was to analyze the pattern and interrelationships among adrenocorticotropic hormone (ACTH), cortisol (CORT), aldosterone (ALD) and electrolytes (sodium—Na+, potassium—K+ and chloride—Cl−) during periovulatory period in cycling mares. Venous blood samples were obtained daily from a total of 23 Purebred Spanish broodmares, aged 7.09 ± 2.5 years, from day −5 to day +5 of estrous cycle, considering day 0, the day of ovulation. Plasma ACTH was measured by a fluorescent immunoassay kit, serum CORT and ALD by means of a competitive ELISA immunoassay, and plasma Na+, K+ and Cl− were quantified by an analyzer with selective electrodes for the three ions. ACTH showed higher concentrations at day 0 compared to days −5 to −1 and +1 to +3 (p < 0.05). CORT showed higher concentrations at day 0 compared to days −5 to −2 and +1 to +5 (p < 0.05). ALD showed higher concentrations at day 0 compared to days −5 to −2 (p < 0.05) and +2 (p < 0.05). Na+ and Cl− showed higher concentrations at day 0, compared to day −5 and +5. K+ showed lower concentrations at day 0 compared to day +1 (p < 0.05). The significant correlations obtained between ACTH and CORT (r = 0.20) and between ACTH and ALD (r = 0.32) suggest that although ACTH may have an effect both on CORT and ALD, there are other very important determinants that could be considered. Hence, it is possible to presume that the pituitary adrenocortical response and ALD may be involved in the ovulatory mechanisms without a direct relation with electrolyte pattern.

Effect of ovariectomy on vasopressin, ACTH, and renin activity responses to hypotension

1991 ◽  
Vol 261 (1) ◽  
pp. R223-R230 ◽  
Author(s):  
M. Keller-Wood ◽  
C. E. Wood
Keyword(s):  
Plasma Renin Activity ◽  
Arginine Vasopressin ◽  
Adrenocorticotropic Hormone ◽  
Plasma Renin ◽  
Renin Activity ◽  
Plasma Acth ◽  
Blood Samples

The gonadal axis is thought to modulate adrenocorticotropic hormone (ACTH), arginine vasopressin (AVP), and plasma renin activity (PRA) responses to stimuli in several species. These experiments were designed to compare the responses to hypotension in chronically ovariectomized ewes and intact ewes. The ewes were infused with nitroprusside at rates of 5, 10, or 15 micrograms.kg-1.min-1 or infused with vehicle for 10 min. The response to 15 micrograms.kg-1.min-1 was also tested with or without treatment with 10 mg of dexamethasone 2 h before nitroprusside. Blood samples were collected before and at 5, 10, 15, 20, and 30 min after the start of the infusion for measurement of plasma ACTH, AVP, and PRA. In both groups of animals there were significant responses to hypotension. There was a significant effect of ovariectomy on ACTH, AVP, and PRA responses. ACTH and PRA responses were lower in the ovariectomized ewes; AVP responses were increased in the ovariectomized ewes. Administration of dexamethasone inhibited ACTH responses and did not inhibit PRA responses in both groups of ewes. Administration of dexamethasone did not inhibit the AVP response in the intact ewes but did reduce the response in the ovariectomized ewes.

ACTH and cortisol responses to hypotension in fetal sheep after a prior CRF injection

1992 ◽  
Vol 262 (3) ◽  
pp. E325-E329
Author(s):  
D. R. Kerr ◽  
M. I. Castro ◽  
N. K. Valego ◽  
N. M. Rawashdeh ◽  
J. C. Rose
Keyword(s):  
Adrenocorticotropic Hormone ◽  
Plasma Acth ◽  
Fetal Sheep ◽  
Feedback Effects ◽  
Maximal Stimulation ◽  
Endogenous Cortisol ◽  
Before And After ◽  
Cortisol Responses ◽  
Releasing Factors ◽  
Stimulation Of

To determine whether an ovine corticotropin-releasing factor (oCRF) injection modifies adrenocorticotropic hormone (ACTH) and cortisol responses to hypotension and whether the effect of any interactions between these stimuli changes across gestation, we studied chronically cannulated fetal lambs of 103-113 ("immature") and 133-139 days gestation ("mature"). Experimental groups received 500 ng/kg oCRF injections and 6 h later had arterial pressure reduced 20% for 10 min with nitroprusside. Blood samples were obtained before and after each manipulation. Controls received vehicle instead of oCRF. The oCRF increased plasma cortisol levels from 2.1 +/- 0.4 to 14.2 +/- 4.7 (SE) ng/ml in immature and 44.9 +/- 2.2 to 102.8 +/- 15 ng/ml in mature animals. In mature fetuses the oCRF did not alter plasma ACTH and cortisol increases due to hypotension. In immature animals ACTH increases were normal but cortisol increases were eliminated. This suggests that the CRF caused maximal stimulation of the adrenal gland. In older fetuses, it appears that the action of ACTH-releasing factors, secreted in response to arterial hypotension, can overcome the negative feedback effects of elevations in endogenous cortisol.

scholarly journals The effect of orally administered Budesonide on the hypothalamic-pituitary-adrenal axis in dogs with inflammatory bowel disease

2017 ◽  
Vol 62 (No. 5) ◽  
pp. 261-268
Author(s):  
A. Rychlik ◽  
M. Nowicki ◽  
A. Kolodziejska-Sawerska ◽  
M. Szweda
Keyword(s):  
Inflammatory Bowel Disease ◽  
Alkaline Phosphatase ◽  
Hpa Axis ◽  
Bowel Disease ◽  
Adrenocorticotropic Hormone ◽  
Chemical Properties ◽  
Activity Levels ◽  
Hypothalamic Pituitary Adrenal ◽  
Inflammatory Bowel ◽  
Biochemical Analyses

The aim of this study was to evaluate the effect of Budesonide on the hypothalamic-pituitary-adrenal (HPA) axis in dogs with inflammatory bowel disease. The effect of orally administered Budesonide (Entocort) on the HPA axis was analysed in 21 dogs with inflammatory bowel disease. Biochemical analyses were carried out to evaluate the activity levels of alanine aminotransferase, asparagine aminotransferase, alkaline phosphatase, cortisol and endogenous adrenocorticotropic hormone. Urine samples were collected from each patient before the study and after 30 days of the experiment to determine the composition and the physical and chemical properties of urine sediments. Considerably lower serum concentrations of cortisol and endogenous adrenocorticotropic hormone were observed after 30 days of treatment. A significant increase in alkaline phosphatase levels was noted on Day 30. In the studied dogs, the drop in HPA axis activity was correlated with side effects associated with the administered glucocorticosteroid (polyuria, polydipsia). In conclusion, we have shown that oral administration of Budesonide to dogs diagnosed with inflammatory bowel disease significantly suppressed the activity of the HPA axis.

Antidepressant‐like effects of quercetin in diabetic rats are independent of hypothalamic–pituitary–adrenal axis

2015 ◽  
Vol 28 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Enver Ahmet Demir ◽  
Hasan Serdar Gergerlioglu ◽  
Mehmet Oz
Keyword(s):  
Hpa Axis ◽  
Adrenocorticotropic Hormone ◽  
Experimental Diabetes ◽  
Forced Swim Test ◽  
Plasma Concentrations ◽  
Diabetic Rats ◽  
Hypothalamic Pituitary Adrenal ◽  
Swim Test ◽  
The Family ◽  
Pituitary Adrenal Axis

ObjectiveQuercetin, one of the most potent flavonol in the family of flavonoids, has been shown to have benefits against diabetes and its complications. In the present study, we investigated effects of quercetin on depression-like behaviours and hypothalamic–pituitary–adrenal (HPA) axis in diabetic rats.MethodsExperimental diabetes was induced by using streptozotocin, and either 50 or 100 mg/kg quercetin was intraperitoneally administered for 21 days. Following the last treatment, animals were subjected to the forced swim test, and subsequently, the blood was obtained by cardiac puncture to measure plasma adrenocorticotropic hormone (ACTH) and corticosterone (CORT) levels.ResultsA significant increase of the total immobile time, accompanied by a decrease in the immobility latency, which suggests a depressive status, was observed in diabetic animals that was reversed by the treatment of 50 mg/kg quercetin. However, the higher dose of quercetin (100 mg/kg) was ineffective in alleviating depression-like behaviours. The plasma concentrations of ACTH, and total- and free-CORT were not affected by both doses of quercetin.ConclusionTherefore, we concluded that the antidepressant-like effects of quercetin in diabetes are independent of the HPA axis.

Lipopolysaccharide is able to bypass corticotrophin-releasing factor in affecting plasma ACTH and corticosterone levels: evidence from rats with lesions of the paraventricular nucleus

1992 ◽  
Vol 133 (2) ◽  
pp. 231-236 ◽  
Author(s):  
I. J. Elenkov ◽  
K. Kovács ◽  
J. Kiss ◽  
L. Bertók ◽  
E. S. Vizi
Keyword(s):  
Hpa Axis ◽  
Paraventricular Nucleus ◽  
Physiological Responses ◽  
Plasma Acth ◽  
Experimental Conditions ◽  
Corticotrophin Releasing Factor ◽  
Adrenal System ◽  
Lps Treatment ◽  
Stimulation Of

ABSTRACT Stimulation of the immune system or experimental conditions (bacterial lipopolysaccharide (LPS) treatment) provoke a broad spectrum of physiological responses. It was recently shown that one of them is the activation of the hypothalamic-pituitary-adrenal (HPA) axis. The mechanism and the site or sites through which LPS stimulates the HPA axis are not well understood. To establish whether the effect of bacterial LPS is related in vivo to the presence of hypothalamic hypophysiotrophic peptides (corticotrophin-releasing factor-41, arginine vasopressin, etc.), plasma ACTH and corticosterone levels were monitored in intact and sham-operated rats, and in rats with paraventricular nucleus lesions in order to remove the main source of these neuropeptides. Evidence was obtained that 4 h after treatment, LPS was able to activate the hypophysial-adrenal system in the absence of hypophysiotrophic neuropeptides of paraventricular origin. It is suggested that, in vivo, LPS could have a direct effect on the pituitary gland or that it acts through an extrapituitary, non-paraventricular pathway to activate the HPA axis. Journal of Endocrinology (1992) 133, 231–236

scholarly journals Allopregnanolone reduces neuroendocrine response to acute stressful stimuli in sheep

2020 ◽  
Vol 244 (1) ◽  
pp. 201-211 ◽  
Author(s):  
Tomasz Misztal ◽  
Patrycja Młotkowska ◽  
Elżbieta Marciniak ◽  
Anna Misztal
Keyword(s):  
Hpa Axis ◽  
Adrenocorticotropic Hormone ◽  
Plasma Sample ◽  
Sample Collection ◽  
Plasma Acth ◽  
Movement Restriction ◽  
Stress Control ◽  
Pomc Mrna ◽  
Collection Period ◽  
Hpa Axis Activity

The verified hypothesis assumed that centrally administered neurosteroid, allopregnanolone (AL), could affect basal and/or stress-induced activity of the hypothalamic-pituitary-adrenal (HPA) axis in sheep. Four groups (n = 6 each) of luteal-phase sheep were intracerebroventricularly infused for 3 days with a vehicle without stress (control); a vehicle treated with stressful stimuli (isolation and partial movement restriction) on the third day; AL (4 × 15 µg/60 µL/30 min, at 30-min intervals) treated with stressful stimuli, and AL alone. Simultaneously, the push-pull perfusion of the infundibular nucleus/median eminence and plasma sample collection were performed. After the experiment, the sheep were killed to collect the hypothalamic and anterior pituitary (AP) tissues. Stressful stimuli evoked an increase in the expression of corticotropin-releasing hormone (CRH) and arginine vasopressin (AVP) mRNA in the hypothalamic paraventricular nucleus (PVN), and AVP receptor (V1b) and proopiomelanocortin (POMC) mRNA in the AP; the concentrations of perfusate CRH, and plasma adrenocorticotropic hormone (ACTH) and cortisol compared to controls. Conversely, the expression of the CRH receptor (CRHR1) mRNA in the AP was downregulated. AL decreased the expression of CRH and AVP mRNA in the PVN, and AVPRV1b and POMC mRNA in the AP in stressed sheep, compared to only stressed ones. There was also a reduction in perfusate CRH, and plasma ACTH and cortisol concentrations. AL alone decreased the expression of CRHR1 mRNA in the AP, and plasma cortisol concentration at the beginning of the collection period compared to controls. In conclusion, AL may function centrally as a suppressor of HPA axis activity in stressed sheep.

scholarly journals Neuropeptide S Stimulates the Hypothalamo-Pituitary-Adrenal Axis and Inhibits Food Intake

Endocrinology ◽  
2006 ◽  
Vol 147 (7) ◽  
pp. 3510-3518 ◽  
Author(s):  
Kirsty L. Smith ◽  
Michael Patterson ◽  
Waljit S. Dhillo ◽  
Sejal R. Patel ◽  
Nina M. Semjonous ◽  
...  
Keyword(s):  
Food Intake ◽  
Hpa Axis ◽  
Paraventricular Nucleus ◽  
Arginine Vasopressin ◽  
Lateral Ventricle ◽  
Neuropeptide S ◽  
Plasma Acth ◽  
Vasopressin Release ◽  
Pituitary Adrenal Axis ◽  
Stimulation Of

Neuropeptide S (NPS) is a recently discovered peptide shown to be involved in the modulation of arousal and fear responses. It has also been shown that lateral ventricle administration of NPS causes a significant decrease in food intake. Neuropeptides involved in the modulation of arousal have been shown to be involved in the regulation of the hypothalamo-pituitary adrenal (HPA) axis and food intake. In this study, we have examined the effect of intracerebroventricular (ICV) administration of NPS on behavior, regulation of the HPA axis, and food intake. ICV NPS significantly increased plasma ACTH and corticosterone 10 and 40 min after injection, respectively. A single ICV injection of NPS caused a significant increase in rearing activity as well as ambulatory movement for up to 45 min after injection. We then studied the effect of paraventricular nucleus (PVN) administration of NPS on the regulation of the HPA axis, behavior, and food intake. There was a significant increase in plasma ACTH and corticosterone after a single NPS PVN injection. Incubation of hypothalamic explants with increasing concentrations of NPS caused a significant increase in CRH and arginine vasopressin release. In addition, PVN administration of NPS dose-dependently inhibited food intake in the first hour after injection, although no effect on food intake was seen after this time. PVN administration of NPS caused a significant increase in rearing activity. These data demonstrate a novel role for NPS in the stimulation of the HPA axis.

scholarly journals Is the plasma ACTH concentration a reliable parameter in the insulin tolerance test?

2003 ◽  
pp. 535-541 ◽  
Author(s):  
K Borm ◽  
M Slawik ◽  
L Seiler ◽  
F Flohr ◽  
M Petrick ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Healthy Subjects ◽  
Peak Plasma ◽  
Tolerance Test ◽  
Insulin Tolerance Test ◽  
Cortisol Concentration ◽  
Plasma Acth ◽  
Hypothalamic Pituitary Adrenal ◽  
Insulin Tolerance ◽  
Acth Concentration

OBJECTIVE: The insulin tolerance test (ITT) is an established standardized test for the evaluation of the hypothalamic-pituitary-adrenal axis. While a peak cortisol value of >18 microg/dl is usually interpreted as a sufficient response to the ITT, the plasma ACTH response has not yet been standardized. METHODS: We evaluated retrospectively the peak plasma ACTH concentrations during 140 ITTs in 125 patients with suspected pituitary insufficiency and prospectively in 15 healthy subjects. RESULTS: All healthy subjects had a peak cortisol concentration >/=18 microg/dl; 32 of 125 tests in the patients showed an insufficient cortisol response (peak cortisol concentration <18 microg/dl). The peak stimulated ACTH concentration in patients with secondary adrenal insufficiency (SAI) was 49.2+/-37.2 pg/ml (mean+/-s.d.) vs 130.9+/-89.3 pg/ml in patients without SAI, and 110.9+/-55.4 pg/ml in normal subjects (P<0.001). There was a weak, but significantly positive correlation between the peak ACTH and peak cortisol concentrations (rho=0.446, P<0.001), but there was also a very wide spread of the values. Defining a cut-off value for the peak plasma ACTH concentration with a sufficient sensitivity and specificity to identify patients with an impaired hypothalamic-pituitary-adrenal (HPA) axis was not possible. A peak plasma ACTH <20 pg/ml as a cut-off value had a sensitivity of 25% and a specificity of 98% for SAI. A cut-off value of a peak plasma ACTH <140 pg/ml had a sensitivity of 97% but a low specificity of 39%. CONCLUSIONS: Although there is a significant positive correlation between the peak ACTH and the peak cortisol concentrations, we conclude that there is no additional benefit in determining the ACTH concentrations during an ITT. Because of the strong variations of the values, the peak ACTH concentration is a poor parameter for the evaluation of the HPA axis.

scholarly journals Impact of hydrocortisone and of CRH infusion on the hypothalamus-pituitary-adrenocortical axis of septic male mice

Endocrinology ◽  
2021 ◽  
Author(s):  
Arno Téblick ◽  
Lauren De Bruyn ◽  
Tim Van Oudenhove ◽  
Sarah Vander Perre ◽  
Lies Pauwels ◽  
...  
Keyword(s):  
Adrenal Cortex ◽  
Plasma Cortisol ◽  
Adrenocorticotropic Hormone ◽  
Ex Vivo ◽  
High Plasma ◽  
Plasma Acth ◽  
Markers Of Inflammation ◽  
Equimolar Dose ◽  
And Function ◽  
Stimulation Of

Abstract Purpose Sepsis is hallmarked by high plasma cortisol/corticosterone (CORT), low adrenocorticotropic hormone (ACTH) and high pro-opiomelanocortin (POMC). While corticotropin-releasing hormone-(CRH) and arginine-vasopressin-(AVP) driven pituitary POMC expression remains active, POMC processing into ACTH becomes impaired. Low ACTH is accompanied by loss of adrenocortical structure, although steroidogenic enzymes remain expressed. We hypothesized that treatment of sepsis with hydrocortisone (HC) aggravates this phenotype whereas CRH infusion safeguards ACTH-driven adrenocortical structure. Methods In a fluid-resuscitated, antibiotics-treated mouse model of prolonged sepsis, we compared the effects of HC and CRH infusion with placebo, on plasma ACTH, POMC and CORT and on markers of hypothalamic CRH and AVP signaling and pituitary POMC processing, and on the adrenocortical structure and markers of steroidogenesis. In adrenal explants, we studied the steroidogenic capacity of POMC. Results During sepsis, HC further suppressed plasma ACTH, but not POMC, predominantly by suppressing sepsis-activated CRH/AVP-signaling pathways. In contrast, in CRH-treated sepsis, plasma ACTH was normalized following restoration of pituitary POMC processing. The sepsis-induced rise in markers of adrenocortical steroidogenesis was unaltered by CRH and suppressed partially by HC which also increased adrenal markers of inflammation. Ex vivo stimulation of adrenal explants with POMC increased CORT as effectively as an equimolar dose of ACTH. Conclusions Treatment of sepsis with HC impaired integrity and function of the HPA axis at the level of the pituitary and the adrenal cortex while CRH restored pituitary POMC processing without affecting the adrenal cortex. Sepsis-induced high circulating POMC may be responsible for ongoing adrenocortical steroidogenesis despite low ACTH.

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