scholarly journals Endocrinological and Behavioural Effects of Chronic Fluxilan Administration in Rats

2007 ◽  
Vol 26 (4) ◽  
pp. 274-279 ◽  
Author(s):  
Nataša Spasojević ◽  
Ljubica Gavrilović ◽  
Ivan Kovačević ◽  
Slađana Dronjak

Endocrinological and Behavioural Effects of Chronic Fluxilan Administration in RatsChronic stress induces changes in the neuroendocrine and neuronal system, including elevation of catecholamines and corticosterone (CORT) levels, and could be an important factor in initial depression. Antidepressants affect monoaminergic neurotransmission and modulate central neuropeptides involved in the coordination of stress response and the control of HPA axis activity. We studied the effects of chronic treatment with fluxilan, a selective inhibitor of serotonin reuptake, in unstressed controls and chronic unpredictable mild stress (CUMS) rats, on behaviour and plasma noradrenaline (NA), adrenaline (A), corticosterone (CORT) and adrenocorticotropic hormone (ACTH). CUMS did not affect plasma NA, A and ACTH, but elevated plasma CORT content. Plasma concentration of catecholamines after fluxilan administration was significantly increased in control and CUMS group. On the other hand, fluxilan expressed no effect on plasma ACTH and CORT concentrations in control animals, but decreased ACTH and CORT levels in CUMS animals. Behaviourally, fluxilan treated animals displayed enhanced anxiety. The results demonstrate that the anxiogenic effects of chronic fluxilan administration are similar to those reported by many other studies. The findings described here suggest that elevated plasma catecholamines may contribute to an adverse effect of this drug on cardiovascular parameters during antidepressant therapy.

1992 ◽  
Vol 263 (4) ◽  
pp. R762-R769 ◽  
Author(s):  
V. L. Brooks ◽  
L. C. Keil

Angiotensin II (ANG II) and vasopressin participate in baroreflex regulation of adrenocorticotropic hormone (ACTH), glucocorticoid, and renin secretion. The purpose of this study was to determine whether this participation is enhanced in water-deprived dogs, with chronically elevated plasma ANG II and vasopressin levels, compared with water-replete dogs. The baroreflex was assessed by infusing increasing doses of nitroprusside (0.3, 0.6, 1.5, and 3.0 micrograms.kg-1.min-1) in both groups of animals. To quantitate the participation of ANG II and vasopressin, the dogs were untreated or pretreated with the competitive ANG II antagonist saralasin, a V1-vasopressin antagonist, or combined V1/V2-vasopressin antagonist, either alone or in combination. The findings were as follows. 1) Larger reflex increases in ANG II, vasopressin, and glucocorticoids, but not ACTH, were produced in water-deprived dogs compared with water-replete dogs. 2) ANG II blockade blunted the glucocorticoid and ACTH responses to hypotension in water-deprived dogs, but not water-replete dogs. In contrast, vasopressin blockade reduced the ACTH response only in water-replete dogs. 3) Vasopressin or combined vasopressin and ANG II blockade reduced the plasma level of glucocorticoids related either to the fall in arterial pressure or to the increase in plasma ACTH concentration in water-replete dogs, and this effect was enhanced in water-deprived dogs. 4) In both water-deprived and water-replete animals, saralasin and/or a V1-antagonist increased the renin response to hypotension, but a combined V1/V2-antagonist did not. These results reemphasize the importance of endogenous ANG II and vasopressin in the regulation of ACTH, glucocorticoid, and renin secretion.(ABSTRACT TRUNCATED AT 250 WORDS)


2020 ◽  
Vol 244 (1) ◽  
pp. 201-211 ◽  
Author(s):  
Tomasz Misztal ◽  
Patrycja Młotkowska ◽  
Elżbieta Marciniak ◽  
Anna Misztal

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.


1995 ◽  
Vol 82 (5) ◽  
pp. 879-885 ◽  
Author(s):  
Are Helseth ◽  
Egil Haug ◽  
Jahn M. Nesland ◽  
Gene P. Siegal ◽  
Øystein Fodstad ◽  
...  

✓ The authors have analyzed several endocrine and metabolic parameters in polyoma large T transgenic mice (PyLT-1) that develop adrenocorticotropic hormone (ACTH)-immunoreactive pituitary tumors and in nontransgenic mice with tumor transplants. All clinically ill PyLT-1 mice (13 to 16 months of age) had pituitary macroadenomas and elevated plasma ACTH levels. Compared to PyLT-1 transgenic mice, the ACTH plasma concentrations in immunocom-petent mice with transplant tumors were markedly raised. In these animals, a secondary effect of hypercorticotropism was documented by a moderate hyperglycemia. Furthermore, mice with transplant tumors had a pathological weight increase from the time the tumor was palpable. The present study supports and extends the authors' previous morphological documentation of the similarity between the ACTH-producing tumors in this mouse model and human Cushing's disease.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 520 ◽  
Author(s):  
Katiuska Satué ◽  
Esterina Fazio ◽  
Ana Muñoz ◽  
Pietro Medica

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.


Author(s):  
Jing-Hua Zhang ◽  
Hui-Zeng Yang ◽  
Hao Su ◽  
Jun Song ◽  
Yu Bai ◽  
...  

Rhizoma coptidis(Huang-lian) and Asian ginseng have been widely used in the treatment of diabetes and other concurrent diseases with apparent effects. This study investigated the effects of the active ingredients of R. coptidis and ginseng, berberine and ginsenoside Rb1, on depression-like behavior in a rat diabetes model. The animal model was established via a high-fat diet and intraperitoneal injection of streptozotocin, while the animal’s depression-like behavior was induced via chronic unpredictable mild stress. These experimental rats were divided into four groups: control, depression-like behavior (DLB), metformin plus fluoxetine hydrochloride (M+FH), and berberine plus ginsenoside Rb1 (B+GRb1) groups. Glucose metabolism and insulin resistance were evaluated by oral glucose test and glucose clamp study. Depression-like behavior was evaluated via behavioral analyses, including forced swim, sucrose preference, elevated plus maze, and open-field tests. HE and Nissl staining, plasma cortisol expression of adrenocorticotropic hormone, and brain-derived neurotrophic factor (BDNF) levels were assayed to explore the mechanisms of action. Compared with the control, rats in the DLB group had a significant increase in the levels of blood glucose and depression-like behavior. The B+GRb1 group significantly improved glucose metabolism and insulin resistance, reduced depression-like behavior, downregulated levels of plasma cortisol and adrenocorticotropic hormone under stress, and upregulated BDNF protein expression compared to the DLB rats. HE and Nissl staining data revealed that B+GRb1 protected neurons from pathological and morphological changes. Thus, berberine and ginsenoside Rb1 not only improved glucose metabolism in diabetic rats but also ameliorated their depression-like behavior under chronic unpredictable stress. Mechanistically, studied data with plasma hormonal levels and brain neuronal pathological/morphological changes supported the observed effects. The combination of berberine and ginsenoside Rb1 may have a clinical value in the management of diabetic patients with depression.


1986 ◽  
Vol 250 (1) ◽  
pp. E87-E93
Author(s):  
W. C. Engeland

Comparisons of resting plasma adrenocorticotropin (ACTH) and corticosterone in the morning and afternoon were made among adult rats bearing regenerated adult adrenal grafts, neonatal (day 1) adrenal grafts, adult adrenal capsule grafts, or intact adrenals. In the morning plasma ACTH and corticosterone were similar in all rats. In the afternoon, plasma ACTH was elevated in rats bearing neonatal adrenal grafts or adult adrenal capsule grafts, but not in rats bearing whole adult adrenal grafts. There was no difference in afternoon plasma corticosterone among rats bearing transplanted adrenals, although afternoon plasma corticosterone was decreased in rats bearing transplants compared with rats with intact adrenals. Thus the increased plasma ACTH after adrenal transplantation cannot be explained entirely by decreases in resting plasma corticosterone. Adrenal responsiveness to ACTH was tested at 5 wk after transplantation in the afternoon by measuring the plasma corticosterone response to submaximal doses of ACTH. The responsiveness was decreased in rats bearing transplants. In addition, responsiveness was inversely related to the age of the grafted adrenal tissue. Adrenals regenerated from adult adrenals were more responsive than adrenals regenerated either from neonatal adrenals or from adult adrenal capsules. The findings suggest that following adrenal transplantation reestablishment of normal pituitary-adrenocortical function does not occur in rats bearing adrenals regenerated from immature adrenal cells. In addition, comparable alterations occur after regeneration of adrenal tissue from neonatal adrenal cells and adult adrenal capsular cells. Elevated plasma ACTH associated with adequate plasma corticosterone in rats bearing adrenals regenerated from immature adrenal cells may result from chronic alteration in responsiveness to steroid feedback.(ABSTRACT TRUNCATED AT 250 WORDS)


2020 ◽  
pp. 1098612X2092568
Author(s):  
Antonio M Tardo ◽  
Claudia E Reusch ◽  
Sara Galac ◽  
Sofia Fornetti ◽  
Alessandro Tirolo ◽  
...  

Objectives The aims of this study were to validate a commercially available chemiluminescent assay for measurement of feline plasma adrenocorticotropic hormone concentration (ACTH), to determine the normal reference interval (RI) of plasma ACTH in healthy cats, to assess plasma ACTH in cats with naturally occurring hypercortisolism (HC), primary hypoadrenocorticism (PH) and other diseases (OD), and to evaluate the effect of aprotinin on plasma ACTH degradation. Methods Forty healthy cats, 10 with HC, 11 with PH and 30 with OD, were included. The chemiluminescent enzyme immunometric assay was evaluated by measurement of intra-assay precision, interassay precision and linearity. The RI for plasma ACTH in healthy cats was established using robust methods. Plasma ACTH of samples collected with and without aprotinin, stored at 4°C and assayed over a 6-day period, was measured. Results The intra-assay coefficients of variance (CVs) ranged from 2.7% to 4.3% and interassay CVs from 3.3% to 10.7%. Dilution studies showed excellent accuracy (R2 >0.99). The RI for plasma ACTH in healthy cats was 32–370 pg/ml. Plasma ACTH was not significantly different between healthy cats and the OD group. Cats with pituitary-dependent hypercortisolism (PDH) and PH had significantly higher plasma ACTH than the other groups. Plasma ACTH did not show significant differences when samples collected with and without aprotinin were compared. Conclusions and relevance The Immulite chemiluminescent assay is a valid technique for measuring plasma ACTH in cats and the RI of plasma ACTH is quite wide. Owing to the low overlap between healthy or OD cats and cats with HC or PH, the measurement of plasma ACTH appears to be useful and should be included in the diagnostic work-up when HC or PH are suspected. Furthermore, the measurement of plasma ACTH may be an accurate test for differentiating PDH from adrenal-dependent hypercortisolism.


1991 ◽  
Vol 261 (1) ◽  
pp. R223-R230 ◽  
Author(s):  
M. Keller-Wood ◽  
C. E. Wood

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.


2019 ◽  
Vol 2 (3) ◽  
pp. 128-131 ◽  
Author(s):  
Nobuaki Shimizu ◽  
Masaru Hasumi ◽  
Tatsuya Hamano ◽  
Misa Iijima ◽  
Takako Yoshioka ◽  
...  

2019 ◽  
Vol 31 (4) ◽  
pp. 585-587 ◽  
Author(s):  
Kayla N. Shepard ◽  
John C. Haffner ◽  
Dwana L. Neal ◽  
Steven T. Grubbs ◽  
Greg L. Pearce

Plasma adrenocorticotropic hormone (ACTH) concentration is used in the diagnosis of pituitary pars intermedia dysfunction (PPID) in horses. We enrolled 10 horses, 5 PPID-positive and 5 PPID-negative, in our study, September 20–22, 2016. On day 0, 5 mL of whole blood was collected into each of 6 EDTA tubes and immediately placed in a refrigerator at 7°C. One tube was centrifuged within 15 min of collection, followed by centrifugation of one tube from each horse at 4, 8, 12, 24, and 36 h following collection. At each time, centrifuged plasma was pipetted into 1.5-mL polypropylene tubes and stored at −80°C. None of the plasma samples were turbid, hemolyzed, or icteric. Plasma was shipped frozen with cold packs overnight to the Animal Health Diagnostic Center of Cornell University (Ithaca, NY) for analysis. The percent change from baseline (PCFB) was reported to standardize the data given that baseline values differed. The mean PCFB was 2.8 (95% confidence interval: –2.9%, 7.0%). Neither refrigeration of whole blood for up to 36 h prior to centrifugation nor freezing affected plasma ACTH concentrations significantly.


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