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Gasco V, Bima C, Geranzani A, Giannelli J, Marinelli L, Bona C, Cambria V, Berton AM, Prencipe N, Ghigo E, Maccario M, Grottoli S. Morning Serum Cortisol Level Predicts Central Adrenal Insufficiency Diagnosed by Insulin Tolerance Test. Neuroendocrinology 2021; 111:1238-1248. [PMID: 33406519 DOI: 10.1159/000514216] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Accepted: 01/05/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION According to guidelines, a morning serum cortisol level <83 nmol/L is diagnostic for central adrenal insufficiency (CAI), a value >414 nmol/L excludes CAI, while values between 83 and 414 nmol/L require stimulation tests. However, there are no currently reliable data on morning serum cortisol for prediction of cortisol response to insulin tolerance test (ITT). OBJECTIVE Using the receiver-operating characteristic curve analysis, the purpose of this study was to detect the morning serum cortisol cutoff with a specificity (SP) or a sensitivity (SE) above 95% that identify those patients who should not be tested with ITT. METHODS We included 141 adult patients (83 males) aged 42.7 ± 12.3 (mean ± standard deviation) years old. Based on the serum cortisol response to ITT, patients have been divided into 2 groups: subjects with CAI (peak serum cortisol <500 nmol/L; 65 patients) and subjects with preserved adrenocortical function (peak cortisol >500 nmol/L; 76 patients). RESULTS The best morning cortisol cutoff, in terms of SE (87.7%) and SP (46.1%), was ≤323.3 nmol/L. The cutoff of morning serum cortisol concentration that best predicted a deficient response to ITT was ≤126.4 nmol/L (SE 13.8%, SP 98.7%). The cutoff of morning serum cortisol concentration that best predicted a normal response to ITT was >444.7 nmol/L (SE 96.9%, SP 14.5%). CONCLUSIONS This is the first study that identifies a morning serum cortisol cutoff that best predict the response to ITT in order to simplify the diagnostic process in patients with suspected CAI. A new diagnostic flow-chart for CAI is proposed.
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Affiliation(s)
- Valentina Gasco
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Chiara Bima
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Alice Geranzani
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Jacopo Giannelli
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Lorenzo Marinelli
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Chiara Bona
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Valeria Cambria
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Alessandro Maria Berton
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Nunzia Prencipe
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Ezio Ghigo
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy,
| | - Mauro Maccario
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
| | - Silvia Grottoli
- Division of Endocrinology, Diabetes and Metabolism, Department of Medical Science, University of Turin, Turin, Italy
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Badawy AAB. Modulation of Tryptophan and Serotonin Metabolism as a Biochemical Basis of the Behavioral Effects of Use and Withdrawal of Androgenic-Anabolic Steroids and Other Image- and Performance-Enhancing Agents. Int J Tryptophan Res 2018; 11:1178646917753422. [PMID: 29487480 PMCID: PMC5821294 DOI: 10.1177/1178646917753422] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 10/29/2017] [Indexed: 01/01/2023] Open
Abstract
Modulation of tryptophan (Trp) metabolism may underpin the behavioral effects of androgenic-anabolic steroids (AAS) and associated image and performance enhancers. Euphoria, arousal, and decreased anxiety observed with moderate use and exercise may involve enhanced cerebral serotonin synthesis and function by increased release of albumin-bound Trp and estrogen-mediated liver Trp 2,3-dioxygenase (TDO) inhibition and enhancement of serotonin function. Aggression, anxiety, depression, personality disorders, and psychosis, observed on withdrawal of AAS or with use of large doses, can be caused by decreased serotonin synthesis due to TDO induction on withdrawal, excess Trp inhibiting the 2 enzymes of serotonin synthesis, and increased cerebral levels of neuroactive kynurenines. Exercise and excessive protein and branched-chain amino acid intakes may aggravate the effects of large AAS dosage. The hypothesis is testable in humans and experimental animals by measuring parameters of Trp metabolism and disposition and related metabolic processes.
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Affiliation(s)
- Abdulla A-B Badawy
- Cardiff School of Health Sciences, Cardiff Metropolitan University, Cardiff, UK
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Garrahy A, Agha A. How should we interrogate the hypothalamic-pituitary-adrenal axis in patients with suspected hypopituitarism? BMC Endocr Disord 2016; 16:36. [PMID: 27316460 PMCID: PMC4912809 DOI: 10.1186/s12902-016-0117-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 06/06/2016] [Indexed: 02/05/2023] Open
Abstract
Hypopituitarism is deficiency of one or more pituitary hormones, of which adrenocorticotrophic hormone (ACTH) deficiency is the most serious and potentially life-threatening. It may occur in isolation or, more commonly as part of more widespread pituitary failure. Diagnosis requires demonstration of subnormal cortisol rise in response to stimulation with hypoglycemia, glucagon, ACTH(1-24) or in the setting of acute illness. The choice of diagnostic test should be individualised for the patient and clinical scenario. A random cortisol and ACTH level may be adequate in making a diagnosis in an acutely ill patient with a suspected adrenal crisis e.g. pituitary apoplexy. Often however, dynamic assessment of cortisol reserve is needed. The cortisol response is both stimulus and assay- dependent and normative values should be derived locally. Results must be interpreted within clinical context and with understanding of potential pitfalls of the test used.
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Affiliation(s)
- Aoife Garrahy
- Division of Endocrinology, Beaumont Hospital, Dublin, Ireland
| | - Amar Agha
- Division of Endocrinology, Beaumont Hospital, Dublin, Ireland.
- RCSI Medical School, Dublin, Ireland.
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Simsek Y, Karaca Z, Tanriverdi F, Unluhizarci K, Selcuklu A, Kelestimur F. A comparison of low-dose ACTH, glucagon stimulation and insulin tolerance test in patients with pituitary disorders. Clin Endocrinol (Oxf) 2015; 82:45-52. [PMID: 24953859 DOI: 10.1111/cen.12528] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2014] [Revised: 05/22/2014] [Accepted: 06/11/2014] [Indexed: 11/28/2022]
Abstract
CONTEXT Diagnosis of secondary adrenal insufficiency and GH deficiency requires evaluation by dynamic stimulation tests in most cases. Although insulin tolerance test (ITT) is accepted as the gold-standard test for the evaluation of both hypothalamo-pituitary-adrenal (HPA) and (GH)-IGF-1 axes, the test is cumbersome. In clinical practice, low-dose adrenocorticotrophic hormone (ACTH) stimulation test is a sensitive, safe and easily applicable alternative to ITT. Although it takes more time, glucagon stimulation test (GST) is also a good alternative to ITT and can evaluate both axes. OBJECTIVE The primary aim of this study was to compare the ITT, low-dose ACTH and GSTs in the evaluation of HPA and GH-IGF-1 axes in patients with pituitary disorders and to evaluate the repeatability of all three tests. DESIGN ITT, low-dose ACTH and GSTs were performed in all 129 patients, and the tests were repeated in 66 of these patients. SETTING Erciyes University Medical School, Department of Endocrinology. PATIENTS OR OTHER PARTICIPANTS One hundred and twenty-nine adult patients (76 women, 53 men) with pituitary disorder were included in the study. MAIN OUTCOME MEASURE(S) The cortisol and GH responses of patients to dynamic tests. RESULTS Peak cortisol levels obtained during ITT were significantly lower than the values obtained during both low-dose ACTH and GSTs. Peak cortisol levels obtained during the GST were lower than those found during the low dose ACTH stimulation test. Peak GH responses were found to be higher in GST than in ITT. All three tests had good reproducibility. CONCLUSIONS Any of 3 tests can be used in the evaluation of the HPA axis and either GST or the ITT can be used in the evaluation of the GH-IGF-1 axis but cut-off levels for the insufficiency of HPA or GH-IGF-1 axis should be individualized for each test.
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Affiliation(s)
- Y Simsek
- Department of Endocrinology, Erciyes University Medical School, Kayseri, Turkey
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Karpman MS, Neculau M, Dias VC, Kline GA. Defining adrenal status with salivary cortisol by gold-standard insulin hypoglycemia. Clin Biochem 2013; 46:1442-6. [DOI: 10.1016/j.clinbiochem.2013.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 04/26/2013] [Accepted: 05/03/2013] [Indexed: 10/26/2022]
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Kopczak A, von Rosen F, Krewer C, Schneider HJ, Stalla GK, Schneider M. Differences in the insulin tolerance test in patients with brain damage depending on posture. Eur J Endocrinol 2011; 164:31-6. [PMID: 20980438 DOI: 10.1530/eje-10-0821] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE The insulin tolerance test (ITT) is the gold standard for the diagnosis of GH deficiency (GHD) and hypocortisolism. As hypopituitarism is a common disorder after traumatic brain injury (TBI) and subarachnoid hemorrhage (SAH), the test is increasingly used in patients with pre-existing brain damage. DESIGN A cross-sectional, observational study. METHODS Fifty-six patients (41 TBI and 15 SAH) were tested with the ITT (0.15 IE/kg body weight, mean glucose 33 mg/dl). In 38 patients, the test was performed in a supine position; the other 18 patients were in a sitting position during the ITT. RESULTS Hypocortisolism and GHD were more often diagnosed in a supine than in a sitting position (hypocortisolism: 55.3% supine versus 0% sitting, P<0.0001; GHD: 42.1% supine versus 11.1% sitting, P=0.03). Patients in a sitting position suffered more often from symptoms such as tachycardia (61.1% sitting versus 15.8% supine, P=0.001), trembling (22.2 vs 7.9%, NS), and sweating (66.7 vs 28.9%, P=0.007). There were no significant differences between the groups in drowsiness (72.2% sitting versus 65.8% supine, NS), dizziness (44.4 vs 44.7%, NS), and fatigue (33.3 vs 15.8%, NS). Because of somnolence, the hypoglycemic state could only be stopped with i.v. administration of glucose in 25 supine patients (66%). In contrast, none of the 18 patients (0%) tested in a sitting position got somnolent or was in need of i.v. application of glucose (P<0.001). CONCLUSIONS In patients with brain injury, posture might affect rates of diagnosing GHD and hypocortisolism and sympathetic symptoms in the ITT. These findings are exploratory and need replication in a standardized setting.
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Affiliation(s)
- A Kopczak
- Schön Klinik Bad Aibling, Kolbermoorer Straße 72, 83043 Bad Aibling, Germany
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Petersenn S, Quabbe HJ, Schöfl C, Stalla GK, von Werder K, Buchfelder M. The rational use of pituitary stimulation tests. DEUTSCHES ARZTEBLATT INTERNATIONAL 2010; 107:437-43. [PMID: 20644702 DOI: 10.3238/arztebl.2010.0437] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2008] [Accepted: 11/23/2009] [Indexed: 11/27/2022]
Abstract
BACKGROUND Diseases of the pituitary gland can lead to the dysfunction of individual hormonal axes and to the corresponding clinical manifestations. The diagnostic assessment of pituitary function has not yet been standardized. METHODS The members of the Neuroendocrinology Section and the Pituitary Study Group of the German Society for Endocrinology (Deutsche Gesellschaft für Endokrinologie) prepared outlines of diagnostic methods for the evaluation of each of the pituitary hormonal axes. These outlines were discussed in open session in recent annual meetings of the Section and the Study Group. RESULTS For the evaluation of the thyrotropic axis, basal TSH and free T4 usually suffice. For the evaluation of the gonadotropic axis in men, the testosterone level should be measured; if the overall testosterone level is near normal, then calculating the free testosterone level may be additionally useful. In women, an intact menstrual cycle is sufficient proof of normal function. In the absence of regular menstruation, measurement of the basal estradiol and gonadotropin levels aids in the diagnosis of the disturbance. For the evaluation of the adrenocorticotropic axis, the basal cortisol level may be helpful; provocative testing is in many cases necessary for precise characterization. The evaluation of the somato-tropic axis requires provocative testing. Aside from the insulin tolerance test, the GHRH-arginine test has become well established. Reference ranges normed to the body mass index (BMI) are available. CONCLUSION The diagnostic evaluation of pituitary insufficiency should proceed in stepwise fashion, depending on the patient's clinical manifestations and underlying disease. For some pituitary axes, measurement of basal hormone levels suffices; for others, stimulation tests are required. In general, the performance of combined pituitary tests should be viewed with caution.
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Asare K. Diagnosis and treatment of adrenal insufficiency in the critically ill patient. Pharmacotherapy 2007; 27:1512-28. [PMID: 17963461 DOI: 10.1592/phco.27.11.1512] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The reported incidence of adrenal insufficiency varies greatly depending on the population of critically ill patients studied, the test and cutoff levels used, and the severity of illness. Several studies have shown increased mortality in patients with very low or very high baseline cortisol levels. Manifestations of adrenal insufficiency in the critically ill patient are numerous and nonspecific, so clinicians are urged to have a high index of suspicion and be alert to important diagnostic clues, such as hyponatremia, hyperkalemia, and hypotension, that are refractory to fluids and vasopressors without any clear causation. Multiple tests have been developed to diagnose adrenal insufficiency, but the most commonly used test in the intensive care unit is the adrenocorticotropic hormone (ACTH) stimulation test. The low-dose ACTH stimulation test has been shown to be more sensitive and specific than the high-dose test; however, the high-dose test is preferred since the low-dose test has not been validated. Although diagnosing adrenal insufficiency continues to be difficult in the critically ill patient, administration of high-dose corticosteroids, defined as methylprednisolone 30 mg/kg/day or more (or its equivalent), over a short period of time provides no overall benefit and may even be harmful; however, administration of low-dose corticosteroids for a longer duration decreases both the amount of the time that vasopressors are required and mortality at 28 days. Hydrocortisone 200-300 mg/day, administered in divided doses or as a continuous infusion, is the preferred corticosteroid in patients with septic shock and should be started as early as possible. For patients in whom the ACTH stimulation test cannot be given immediately, clinicians are urged to consider using dexamethasone until such time that the test can be administered, since, unlike hydrocortisone, it does not interfere with the cortisol test.
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Affiliation(s)
- Kwame Asare
- Pharmacy Department, St. Thomas Hospital, 4220 Harding Road, Nashville, TN 37202, USA.
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Kloeckner M, Gallet de Saint-Aurin R, Polito A, Aboab J, Annane D. [Corticotropic axis in septic shock]. ANNALES D'ENDOCRINOLOGIE 2007; 68:281-9. [PMID: 17689480 DOI: 10.1016/j.ando.2007.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Affiliation(s)
- M Kloeckner
- Service de réanimation médicale, hôpital Raymond-Poincaré, université de Versailles-Saint-Quentin, 104, boulevard Raymond-Poincaré, 92380 Garches, France
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Klose M, Lange M, Kosteljanetz M, Poulsgaard L, Feldt-Rasmussen U. Adrenocortical insufficiency after pituitary surgery: an audit of the reliability of the conventional short synacthen test. Clin Endocrinol (Oxf) 2005; 63:499-505. [PMID: 16268800 DOI: 10.1111/j.1365-2265.2005.02368.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Assessment of the hypothalamic-pituitary-adrenal (HPA) axis after pituitary surgery is important for appropriate decision making regarding replacement therapy. The synacthen test is often used but is questioned, as time has to elapse for adrenal atrophy to develop. OBJECTIVE To audit the use of the 250 microg synacthen test after transsphenoidal adenomectomy. METHODS A retrospective study of 110 patients submitted to first-time transsphenoidal adenomectomy. Anterior pituitary testing was performed preoperatively, 1 week and 1, 3, 6 and 12 months postoperatively. The adrenocortical function was tested by a synacthen test (250 microg synacthen i.v.). RESULTS Thirty-two out of 71 patients with normal HPA function before surgery developed insufficiency postoperatively, seven patients presenting an insufficient test response after 1 week, 16 after 1 month and nine after 3 months, whereas none became insufficient during the remaining follow-up. Three patients presented symptomatic adrenal insufficiency during the first postoperative week despite a normal test. All of these developed an insufficient test 1 month postoperatively. A 1-week basal plasma cortisol > 400 nmol/l indicated HPA sufficiency, whereas a basal cortisol < or = 100 nmol/l indicated insufficiency when related to the diagnosis based on the 3-month synacthen test. CONCLUSION This study confirms that the synacthen test is of limited use in the early postoperative phase, because out of 62 patients with normal 1-week postoperative synacthen responses, 23 patients developed a test that was indicative of adrenal insufficiency over 1-3 months. Our results indicate that a large proportion of patients should be considered for hydrocortisone replacement therapy up to 3 months postoperatively followed by reassessment of the HPA axis.
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Affiliation(s)
- M Klose
- Department of Medical Endocrinology, Copenhagen University Hospital, Denmark.
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Kennan RP, Takahashi K, Pan C, Shamoon H, Pan JW. Human cerebral blood flow and metabolism in acute insulin-induced hypoglycemia. J Cereb Blood Flow Metab 2005; 25:527-34. [PMID: 15703703 DOI: 10.1038/sj.jcbfm.9600045] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
How the human brain functions under conditions of acute hypoglycemia remains a complex question by virtue of the potential simultaneous shifts in processes of perfusion, metabolism, and changing demand. We examined this issue by measuring cerebral blood flow (CBF) and oxidative metabolism (CMRO2) in insulin-induced hypoglycemic (HG) and euglycemic (EG) conditions at rest and during motor activation in normal human subjects using magnetic resonance (MR). Experiments were performed on 12 subjects (9M, 3F). The protocol consisted of insulin-induced hypoglycemia (targeting a HG of 60 mg/dL) followed by euglycemia, or in reverse order, each phase lasting approximately 1.5 h. Euglycemia was performed with the same insulin infusion rate so as to match the hypoglycemic phase. Magnetic resonance data were acquired 30 mins after the target plasma glucose was achieved so as to minimize any acute effects. Although the depth of hypoglycemia achieved in the present study was relatively small, the present data found a significant increase in flow in motor cortex with mild hypoglycemia, from 56.4+/-13.6 mL/100 g min (euglycemia) to 64.3+/-7.6 mL/100 g min (hypoglycemia). Using the Renkin-Crone exponential model of oxygen extraction with MR models of susceptibility-based relaxation, analysis of the flow measurements, relaxation and BOLD data also implied that throughout the studies, metabolism and flow remained coupled. Elementary motor task activation was not associated with any consistent larger activated flows. Thus it remains that although mild hypoglycemia induced an increase in basal flow and metabolism, a similar increase was not seen in task activation.
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Affiliation(s)
- Richard P Kennan
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Ruiter M, La Fleur SE, van Heijningen C, van der Vliet J, Kalsbeek A, Buijs RM. The daily rhythm in plasma glucagon concentrations in the rat is modulated by the biological clock and by feeding behavior. Diabetes 2003; 52:1709-15. [PMID: 12829637 DOI: 10.2337/diabetes.52.7.1709] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Plasma glucose concentrations display a daily rhythm generated by the hypothalamic biological clock, located in the suprachiasmatic nucleus (SCN). How the SCN orchestrates this rhythm is unknown. Because glucagon stimulates hepatic glucose production, we hypothesized that if glucagon has a daily rhythm, then it may be responsible for the glucose rhythm. From hourly blood samples, we determined daily glucagon concentrations for intact and SCN-lesioned rats. Intact ad libitum-fed rats showed a clear daily glucagon rhythm, and fasting resulted in an even more pronounced rhythm. It is interesting that a decrease in glucagon concentrations, instead of the expected increase, occurred already shortly after food removal. Toward the start of the active period, a peak in glucagon levels occurred, with concentrations similar to those measured in ad libitum-fed rats. SCN lesions abolished rhythmicity in plasma glucagon profiles. Scheduled-fed rats showed meal-induced glucagon peaks but also a daily rhythm in basal premeal glucagon concentrations. Plasma glucose concentrations of ad libitum-and scheduled-fed rats, however, were similar. In conclusion, feeding and the biological clock control 24-h plasma glucagon concentrations. In fed rats, glucagon is not responsible for the daily glucose rhythm. During fasting, however, glucagon may contribute to energy mobilization when the activity period starts.
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Affiliation(s)
- Marieke Ruiter
- Netherlands Institute for Brain Research, Amsterdam, The Netherlands.
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