Changes in prolactin secretion in the short- and long-term after adrenalectomy

OBJECTIVE: To evaluate the modulation of the hypothalamus-pituitary-adrenal axis (HPA) on prolactin secretion in rats after adrenalectomy (ADX). MATERIALS AND METHODS: Plasma corticosterone, ACTH, and prolactin concentrations were measured by radioimmunoassay in rats after bilateral ADX in the short- (3 hours and 1day) and long-term (3, 7, and 14 days). RESULTS: Animals that underwent ADX showed undetectable corticosterone levels and a triphasic ACTH response with a transient increase (3h), a decrease (1d), and further increase in the long-term after ADX. Sham animals showed a marked increase in corticosterone and ACTH levels three hours after surgery, with a decrease to basal levels thereafter. Plasma prolactin levels were not changed after ADX. CONCLUSION: There are different points of equilibrium in the HPA axis after the glucocorticoid negative feedback is removed. Prolactin plasma secretion is not altered in the short or long- term after ADX, suggesting that the peptidergic neurons essential for prolactin release are not activated after ADX.

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Contribution of Growth Arrest-Specific 5/miR-674 to the Hypothalamus Pituitary Adrenal Axis Regulation Effect by Electroacupuncture following Trauma

NeuroImmunoModulation ◽

10.1159/000513385 ◽

2021 ◽

pp. 1-13

Author(s):

Jing Zhu ◽

Chunxia Guo ◽

Pingping Lu ◽

Shuijin Shao ◽

Bing Tu

Keyword(s):

Hpa Axis ◽

Interleukin 1 ◽

Growth Arrest ◽

Luciferase Assay ◽

Function Evaluation ◽

Protein Levels ◽

Adrenal Axis ◽

Post Surgery ◽

Hypothalamus Pituitary Adrenal Axis ◽

Pituitary Adrenal Axis

Background: Electroacupuncture (EA) can improve trauma-induced hypothalamus pituitary adrenal axis (HPA) hyperactivity. However, the mechanism underlying the EA effect has not been fully understood. Methods and Study Design: This study was undertaken to explore the role of hypothalamic growth arrest-specific 5 (Gas5) in the regulation of EA on HPA axis function post-surgery. Paraventricular nuclear Gas5 levels were upregulated in rats using an intracerebroventricular injection of pAAV-Gas5. Primary hypothalamic neurons and 293T cells were cultured for miRNA and siRNAs detection. Radioimmunoassay, PCR, Western blot, and immunohistochemistry were used for HPA axis function evaluation. Results: The overexpression of Gas5 abolished the effect of EA on the regulation of trauma-induced HPA axis hyperactivity. Using a bioinformatics analysis and dual luciferase assay, we determined that miRNA-674 was a target of Gas5. Additionally, miRNA-674 levels were found to have decreased in trauma rats, and this effect was reversed after EA intervention. TargetScan analysis showed that serum and glucocorticoid inducible kinase 1 (SGK1) were targets of miR-674. Moreover, we found that SGK1 protein levels increased in trauma rats and SGK1 expression inhibition alleviated HPA axis abnormality post-surgery. EA could improve the number of hypothalamus iba-1 positive cells and hypothalamic interleukin 1 beta protein expression. Conclusions: Our study demonstrated the involvement of the hypothalamic Gas5/miRNA-674/SGK1 signaling pathway in EA regulation of HPA axis function after trauma.

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Influence of melatonin and oestradiol on the opioidergic regulation of LH and prolactin release in pony mares

Journal of Endocrinology ◽

10.1677/joe.0.1540241 ◽

1997 ◽

Vol 154 (2) ◽

pp. 241-248 ◽

Cited By ~ 4

Author(s):

C Aurich ◽

J Lange ◽

H-O Hoppen ◽

J E Aurich

Keyword(s):

Prolactin Secretion ◽

Opioid Antagonist ◽

Short Term ◽

Melatonin Treatment ◽

Prolactin Release ◽

Oestradiol Treatment ◽

Oestradiol Benzoate ◽

Lh Release ◽

Lh Secretion

Abstract The aim of this study was to investigate the influence of oestradiol, melatonin and season on the opioid regulation of LH and prolactin release. Effects of the opioid antagonist naloxone (0·5 mg/kg) on LH and prolactin secretion were determined in ovariectomized pony mares. In experiment 1, mares in January (n=6) were pretreated with oestradiol benzoate (5 μg/kg) for 20 days. In experiment 2, beginning in May, mares (n=7) received melatonin (15 mg) for 15 days and subsequently a combination of melatonin plus oestradiol for 20 days. In experiment 3, beginning in May, mares (n=6) were pretreated with oestradiol for 30 days, left untreated for 12 days and then given melatonin for 35 days. In all experiments the animals were injected with the opioid antagonist naloxone and saline on 2 consecutive days prior to treatment. In experiment 1, animals received naloxone and saline on days 10 and 11 and 20 and 21 following oestradiol treatment. In experiment 2, naloxone and saline were administered on days 15 and 16 following melatonin treatment and on days 10 and 11 and 20 and 21 of melatonin plus oestradiol treatment. In experiment 3, the animals received naloxone and saline on days 10 and 11, 20 and 21 and 30 and 31 of oestradiol treatment, prior to melatonin treatment and on days 15 and 16, 25 and 26 and 35 and 36 following melatonin. In January (experiment 1), naloxone evoked a significant (P<0·05) LH release at all times, however the LH increment in response to naloxone increased during oestradiol pretreatment (P<0·05) During the breeding season (experiments 2 and 3), naloxone induced a significant (P<0·05) increase in plasma LH concentrations when mares had not been pretreated with oestradiol or melatonin and after oestradiol pretreatment. Basal LH concentrations and the LH increment in response to naloxone increased significantly (P<0·05) during the 30-day oestradiol pretreatment. Melatonin decreased the naloxone-induced LH release and the LH release in response to naloxone and saline no longer differed after 25 and 35 days of melatonin pretreatment. When melatonin was given together with oestradiol for 20 days, again a significant (P<0·05) LH release in response to naloxone occurred. Prolactin release was significantly (P<0·05) increased by naloxone when mares had been pretreated with only melatonin. The opioid antagonist did not affect prolactin release in mares that had not been pretreated or received oestradiol either alone or in combination with melatonin. In conclusion, in long-term ovariectomized mares, opioids inhibit LH secretion independent from ovarian factors. This opioid inhibition of LH secretion is enhanced by oestradiol and reduced by melatonin. Although short-term melatonin treatment in-activates the opioid regulation of LH release, a prolonged influence of melatonin as occurs in winter does not prevent activation of the opioid system. This indicates that effects of melatonin on the opioid regulation of LH release change with time. An opioid inhibition of prolactin secretion is activated by melatonin given for 15–35 days but is lost under the prolonged influence of a short-day melatonin signal in winter. Journal of Endocrinology (1997) 154, 241–248

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Short- and long-term fluctuations in plasma prolactin concentration in normal subjects

Acta Endocrinologica ◽

10.1530/acta.0.0970001 ◽

1981 ◽

Vol 97 (1) ◽

pp. 1-6 ◽

Cited By ~ 29

Author(s):

Henning Djursing ◽

Claus Hagen ◽

Jan Møller ◽

Claus Christiansen

Keyword(s):

Plasma Concentration ◽

Menstrual Cycle ◽

Normal Subjects ◽

Plasma Prolactin ◽

Menopausal Women ◽

Normal Menstrual Cycle ◽

Basal Plasma ◽

Short And Long Term ◽

Post Menopausal

Abstract. The physiological changes in plasma prolactin concentration were studied in 447 normal subjects, including 65 men, 75 pre-menopausal women and 307 post-menopausal women. The within-day and day-to-day variation as well as the circadian and circannual rhythm of plasma prolactin levels were determined. Furthermore, the relationship between changes in prolactin and oestradiol-17β levels during the normal menstrual cycle and in the climacteric was studied. Pre-menopausal women had significantly (P<0.01) higher basal plasma prolactin concentration than men and post-menopausal women. Furthermore, they had significantly (P < 0.01) higher day-to-day variation than men. This suggests that prolactin in women is secreted in a pulsatile fashion. Only small seasonal variations in both sexes were seen. The levels of plasma prolactin during the ovulatory and the luteal phase in the cycle were significantly (P < 0.02) higher than that of the follicular phase, and a positive correlation between changes in plasma concentration of oestradiol-17β and prolactin was found. Also in post-menopausal women a relationship between plasma concentration of prolactin and oestradiol-17β was seen. It is concluded that the assessment of prolactin concentration in blood is dependent on the physiological variation recorded during sleep in both sexes. However, only in women day-to-day changes and the changes related to the menstrual cycle and the climacteric are of importance.

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Development and amplification of mid-afternoon surges of prolactin secretion in ovariectomized immature rats

Journal of Endocrinology ◽

10.1677/joe.0.1100361 ◽

1986 ◽

Vol 110 (2) ◽

pp. 361-366 ◽

Cited By ~ 3

Author(s):

H. F. Urbanski ◽

S. R. Ojeda

Keyword(s):

Prolactin Secretion ◽

Ovariectomized Rats ◽

Female Rat ◽

Plasma Prolactin ◽

Short Term ◽

Small Magnitude ◽

Neuroendocrine Mechanisms ◽

Phases Of Development ◽

Juvenile Development

ABSTRACT The immature female rat shows a mid-afternoon surge of prolactin secretion which reaches a maximum on the day of first pro-oestrus. The present experiments were undertaken to elucidate the mechanisms which underly the development of this prolactin discharge. Detailed plasma prolactin profiles were obtained from short-term (48 h) ovariectomized rats at 23, 28 or 37 days of age. In the two older groups, but not the youngest, a mid-afternoon surge of prolactin secretion occurred in spite of the absence of the ovaries. To exclude the possibility that such an apparent ovarian-independent discharge of prolactin was due to an oestradiol effect which persisted for 2 days following ovariectomy, another study was conducted using long-term ovariectomized animals. Plasma profiles were obtained from neonatally ovariectomized rats at ages equivalent to juvenile (26–28 days), peripubertal (38–41 days) or adult (46–49 days) phases of development. A mid-afternoon surge of prolactin secretion was observed in the majority of animals (eight out of twelve) irrespective of the interval after ovariectomy; this finding further indicates that in the female rat there is a centrally originated mid-afternoon episode of prolactin secretion which is expressed during juvenile development even in the absence of the ovaries. The relatively small magnitude of these ovarian-independent prolactin discharges (c.f. the preovulatory prolactin surge) suggested that in the intact animal they are amplified by ovarian secretions. To test this hypothesis, oestradiol-containing silicone elastomer capsules were implanted s.c. into juvenile rats, immediately after ovariectomy, and plasma prolactin profiles examined 2 days later (28 days of age). In all cases the prolactin surge was greatly amplified and in many instances the magnitude was identical to that observed at first pro-oestrus. These data suggest that development of the large pro-oestrous surge of prolactin secretion involves the interplay of at least two distinct neuroendocrine mechanisms: (1) a centrally originated ovarian-independent signal and (2) an amplification effect exerted by ovarian oestradiol. J. Endocr. (1986) 110, 361–366

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Shared Pathogenesis in Depression and Cancer Depicting the Anti-cancer Properties of Anti-depressants

Asian Pacific Journal of Cancer Biology ◽

10.31557/apjcb.2021.6.1.3-4 ◽

2021 ◽

Vol 6 (1) ◽

pp. 3-4

Author(s):

Abhijeet Faye

Keyword(s):

Hpa Axis ◽

Cellular Immunity ◽

Inflammatory Markers ◽

Adrenal Axis ◽

Anti Cancer ◽

Psychiatric Conditions ◽

Pituitary Adrenal Axis ◽

Long Term Studies

Pathogenesis of depression is similar to that of cancer in many aspects. Important mechanisms include effects on hypothalamo-pituitary-adrenal axis (HPA axis), functions of prostaglandins, inflammatory markers and cellular immunity. Anti-depressants must have the actions through above mentioned mechanisms when used to treat depression. Literature has mentioned the effects of various anti-depressant agents in reversing or modifying the pathogenic changes that occur in cancer too. It’s worth exploring the anti-cancer properties of anti-depressants and utilize those for the treatment of cancer whenever used for treating associated depression or other psychiatric conditions. Long term studies are needed to prove this less researched aspect of antidepressants.

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Altered Cortisol Metabolism Increases Nocturnal Cortisol Bioavailability in Prepubertal Children With Type 1 Diabetes Mellitus

Frontiers in Endocrinology ◽

10.3389/fendo.2021.742669 ◽

2021 ◽

Vol 12 ◽

Author(s):

Julie Brossaud ◽

Jean-Benoît Corcuff ◽

Vanessa Vautier ◽

Aude Bergeron ◽

Aurelie Valade ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 1 Diabetes ◽

Hpa Axis ◽

Trait Anxiety ◽

Hydroxysteroid Dehydrogenase ◽

Prepubertal Children ◽

Cortisol Metabolism ◽

Hypothalamus Pituitary Adrenal Axis ◽

Pituitary Adrenal Axis

ObjectiveDisturbances in the activity of the hypothalamus-pituitary-adrenal axis could lead to functional alterations in the brain of diabetes patients. In a later perspective of investigating the link between the activity of the hypothalamus-pituitary-adrenal axis and the developing brain in children with diabetes, we assessed here nocturnal cortisol metabolism in prepubertal children with type 1 diabetes mellitus (T1DM).MethodsPrepubertal patients (aged 6–12 years) diagnosed with T1DM at least 1 year previously were recruited, along with matched controls. Nocturnal urine samples were collected, with saliva samples taken at awakening and 30 minutes after awakening. All samples were collected at home over 5 consecutive days with no detectable nocturnal hypoglycaemia. The State-Trait Anxiety Inventory (trait scale only) and Child Depression Inventory were also completed. Glucocorticoid metabolites in the urine, salivary cortisol (sF) and cortisone (sE) were measured by liquid chromatography–tandem mass spectrometry. Metabolic data were analysed by logistic regression, adjusting for sex, age, BMI and trait anxiety score.ResultsUrine glucocorticoid metabolites were significantly lower in T1DM patients compared to controls. 11β-hydroxysteroid dehydrogenase type 1 activity was significantly higher, while 11β-hydroxysteroid dehydrogenase type 2, 5(α+β)-reductase and 5α-reductase levels were all lower, in T1DM patients compared to controls. There was a significant group difference in delta sE level but not in delta sF level between the time of awakening and 30 minutes thereafter.ConclusionsOur findings suggest that altered nocturnal cortisol metabolism and morning HPA axis hyperactivity in children with T1DM leads to greater cortisol bioavailability and lower cortisol production as a compensatory effect. This altered nocturnal glucocorticoid metabolism when cortisol production is physiologically reduced and this HPA axis hyperactivity question their impact on brain functioning.

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Corticosterone, Adrenal, and the Pituitary-Gonadal Axis in Neonatal Rats: Effect of Maternal Separation and Hypoxia

Endocrinology ◽

10.1210/endocr/bqaa085 ◽

2020 ◽

Vol 161 (7) ◽

Author(s):

Ashley L Gehrand ◽

Jonathan Phillips ◽

Kevin Malott ◽

Hershel Raff

Keyword(s):

Maternal Separation ◽

Plasma Corticosterone ◽

Plasma Testosterone ◽

Postnatal Life ◽

Sexually Dimorphic ◽

Long Term Effects ◽

Estrogen Production ◽

Corticosterone Response ◽

Short And Long Term

Abstract Hypoxia, a common stressor in prematurity, leads to sexually dimorphic, short- and long-term effects on the adult hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes. We hypothesized that these effects are due to stress-induced increases in testosterone during early postnatal life. We evaluated this phenomenon by systematically assessing the short-term effects of normoxic or hypoxic separation on male and female pups at birth, postnatal hours (H) 2, 4, and 8, and postnatal days (PD) 2 to 7. Our findings were (a) hypoxic separation led to a large increase in plasma corticosterone from 4H-PD4, (b) neither normoxic nor hypoxic separation affected critical adrenal steroidogenic pathway genes; however, a significant decrease in baseline Cyp11a1, Mc2r, Mrap, and Star adrenal expression during the first week of neonatal life confirmed the start of the adrenal stress hyporesponsive period, (c) a luteinizing hormone/follicle-stimulating hormone–independent increase in plasma testosterone occurred in normoxic and hypoxic separated male pups at birth, (d) testicular Cyp11a1, Lhcgr, and Star expression was high at birth and decreased thereafter suggesting a hyporesponsive period in the testes, and (e) elevated estrogen in the early neonatal period occurred independently of gonadotropin stimulation. We conclude that a large corticosterone response to hypoxia during the first 5 days of life occurs as an adaptation to neonatal stress, that the testosterone surge during the first hours after birth occurs independently of gonadotropins but is associated with upregulation of the steroidogenic pathway genes in the testes, and that high postnatal estrogen production also occurs independently of gonadotropins.

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In adults with obesity, copeptin is linked with BMI but is not associated with long-term exposure to cortisol and cortisone

Acta Endocrinologica ◽

10.1530/eje-20-0077 ◽

2020 ◽

Vol 183 (6) ◽

pp. 669-676

Author(s):

Eline S van der Valk ◽

Bibian van der Voorn ◽

Anand M Iyer ◽

Sjoerd A A van den Berg ◽

Mesut Savas ◽

...

Keyword(s):

Hpa Axis ◽

Scalp Hair ◽

Surrogate Marker ◽

Cross Sectional Study ◽

Hair Cortisol ◽

Cross Sectional ◽

Cardiometabolic Diseases ◽

Important Regulator ◽

Pituitary Adrenal Axis

Context Obesity and cardiometabolic diseases are associated with higher long-term glucocorticoid levels, measured as scalp hair cortisol (HairF) and cortisone (HairE). Cardiometabolic diseases have also been associated with copeptin, a stable surrogate marker for the arginine-vasopressin (AVP) system. Since AVP is, together with corticotropin-releasing hormone (CRH) an important regulator of the hypothalamic-pituitary adrenal axis (HPA axis), we hypothesize that AVP contributes to chronic hypercortisolism in obesity. Objective To investigate whether copeptin levels are associated with Higher HairF and HairE levels in obesity. Design A cross-sectional study in 51 adults with obesity (BMI ≥30 kg/m2). Methods Associations and interactions between copeptin, HairF, HairE, and cardiometabolic parameters were cross-sectionally analyzed. Results Copeptin was strongly associated with BMI and waist circumference (WC) (rho = 0.364 and 0.530, P = 0.008 and <0.001, respectively), also after correction for confounders. There were no associations between copeptin and HairF or HairE on a continuous or dichotomized scale, despite correction for confounders. Conclusion In patients with obesity, AVP seems not a major contributor to the frequently observed high cortisol levels. Other factors which stimulate the HPA axis or affect cortisol synthesis or breakdown may be more important than the influence of AVP on long-term glucocorticoid levels in obesity.

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Lipopolysaccharide has selective actions on sub-populations of catecholaminergic neurons involved in activation of the hypothalamic–pituitary–adrenal axis and inhibition of prolactin secretion

Journal of Endocrinology ◽

10.1677/joe.1.05839 ◽

2005 ◽

Vol 184 (2) ◽

pp. 393-406 ◽

Cited By ~ 22

Author(s):

Jacob H Hollis ◽

Stafford L Lightman ◽

Christopher A Lowry

Keyword(s):

Immune Activation ◽

Plasma Corticosterone ◽

Hypothalamic Pituitary Adrenal Axis ◽

Plasma Prolactin ◽

Hypothalamic Pituitary Adrenal ◽

Adrenal Axis ◽

Neuroendocrine Function ◽

Cell Groups ◽

Neuroendocrine Responses ◽

Pituitary Adrenal Axis

Immune activation results in adaptive neuroendocrine responses, including activation of the hypothalamic–pituitary–adrenal axis, which are dependent on the integrity of medullary catecholaminergic (CA) systems. In contrast, although specific roles of pontine, midbrain, and hypothalamic CA systems in neuroendocrine function have been described, the functional roles of these CA systems in modulating neuroendocrine function during immune responses have not been investigated. We have, therefore, investigated the effects of immune activation on the various CA systems of the central nervous system (CNS) and explored this relationship with changes in plasma corticosterone and plasma prolactin. Male BALB/c mice were injected with lipopolysaccharide (LPS, 500 μg/kg i.p.) and 2 h later cardiac blood was taken and mice were perfused with fixative. Immunostaining procedures were performed using antibodies raised against c-Fos and tyrosine hydroxylase, a marker of CA neurons, and detailed topographical analysis of the CA systems within the CNS was performed. LPS-injected mice had increased concentrations of plasma corticosterone and decreased concentrations of plasma prolactin compared with vehicle-injected controls. LPS-injected mice had increased numbers of c-Fos-positive CA neurons within the medullary (A1, A2, C1, C2), pontine (A6) and midbrain (A10) cell groups when compared with vehicle-injected controls. Among hypothalamic CA cell groups, LPS had differential effects on the numbers of c-Fos-positive CA neurons in topographically organised subdivisions of the arcuate nucleus (A12). Changes in plasma prolactin concentrations correlated with the numbers of c-Fos-positive CA neurons within the area postrema, the medullary CA cell groups, the medial posterior division of the arcuate, and the zona incerta. The present study identifies topographically organised, anatomically distinct CA systems that are likely to modulate some of the neuroendocrine responses to immune activation, and may provide novel targets for the relief of symptoms associated with illness and disease.

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LIGHT-INDUCED RHYTHMS OF PROLACTIN SECRETION IN THE RAM AND THE EFFECT OF CRANIAL SYMPATHECTOMY

Acta Endocrinologica ◽

10.1530/acta.0.0910421 ◽

1979 ◽

Vol 91 (3) ◽

pp. 421-427 ◽

Cited By ~ 9

Author(s):

G. A. Lincoln

Keyword(s):

Prolactin Secretion ◽

Plasma Prolactin ◽

Hormone Concentration ◽

Short Term ◽

Seasonal Rhythms ◽

Artificial Lighting ◽

Long Term Changes ◽

Cervical Ganglia ◽

Short Days

ABSTRACT Four Soay rams cranially sympathectomised by removal of the superior cervical ganglia were housed alongside 4 control rams in an artificial lighting regime of alternating 16 week periods of short days (8L: 16D) and long days (16L: 8D) for 2 years. The variations in the plasma prolactin concentration revealed that while the control animals adjusted both the short term (diurnal) and long term (seasonal) rhythms in prolactin secretion in response to the changes in daylength, the ganglionectomised rams failed to respond. These sympathectomised animals continued to show long term changes in the circulating level of prolactin however and during the periods of hypersecretion a conspicuous diurnal rhythm in the hormone concentration was apparent.

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