caa a22 4500 555311066 20190719030246.0 cr unu---uuuuu 190207e20181001xx s 000 0 eng 2049-3614 10.1530/EC-18-0242 doi (BORIS)oai:boris.unibe.ch:122371 610 ddc 30352395 pmid Adrenal, thyroid and gonadal axes are affected at high altitude [Elektronische Daten] [M. von Wolff, Christos T. Nakas, Marlene Wolf, Tobias Merz, M P Hilty, J D Veldhuis, A R Huber, Jacqueline Renée Pichler Hefti] publishedVersion openAccess eu-repo Humans cannot live at very high altitude for reasons, which are not completely understood. Since these reasons are not restricted to cardiorespiratory changes alone, changes in the endocrine system might also be involved. Therefore, hormonal changes during prolonged hypobaric hypoxia were comprehensively assessed to determine effects of altitude and hypoxia on stress, thyroid and gonadal hypothalamus-pituitary hormone axes. Twenty-one male and 19 female participants were examined repetitively during a high-altitude expedition. Cortisol, prolactin, thyroid-stimulating hormone (TSH), fT4 and fT3 and in males follicle-stimulating hormone (FSH), luteinizing hormone (LH) and total testosterone were analysed as well as parameters of hypoxemia, such as SaO2 and paO2 at 550 m (baseline) (n = 40), during ascent at 4844 m (n = 38), 6022 m (n = 31) and 7050 m (n = 13), at 4844 m (n = 29) after acclimatization and after the expedition (n = 38). Correlation analysis of hormone concentrations with oxygen parameters and with altitude revealed statistical association in most cases only with altitude. Adrenal, thyroid and gonadal axes were affected by increasing altitude. Adrenal axis and prolactin were first supressed at 4844 m and then activated with increasing altitude; thyroid and gonadal axes were directly activated or suppressed respectively with increasing altitude. Acclimatisation at 4844 m led to normalization of adrenal and gonadal but not of thyroid axes. In conclusion, acclimatization partly leads to a normalization of the adrenal, thyroid and gonadal axes at around 5000 m. However, at higher altitude, endocrine dysregulation is pronounced and might contribute to the physical degradation found at high altitude. von Wolff M. joint author Nakas Christos T. joint author Wolf Marlene joint author Merz Tobias joint author Hilty M P. joint author Veldhuis J D. joint author Huber A R. joint author Pichler Hefti Jacqueline Renée joint author Endocrine Connections 7(10), pp. 1081-1089 2049-3614 https://boris.unibe.ch/122371/1/%5B20493614%20-%20Endocrine%20Connections%5D%20Adrenal%2C%20thyroid%20and%20gonadal%20axes%20are%20affected%20at%20high%20altitude.pdf text/html WWW-Backlink auf das Repository 1 info:eu-repo/semantics/article boris PeerReviewed boris peerstatus BORIS 856 40 https://boris.unibe.ch/122371/1/%5B20493614%20-%20Endocrine%20Connections%5D%20Adrenal%2C%20thyroid%20and%20gonadal%20axes%20are%20affected%20at%20high%20altitude.pdf text/html WWW-Backlink auf das Repository BORIS 700 1- von Wolff M. joint author BORIS 700 1- Nakas Christos T. joint author BORIS 700 1- Wolf Marlene joint author BORIS 700 1- Merz Tobias joint author BORIS 700 1- Hilty M P. joint author BORIS 700 1- Veldhuis J D. joint author BORIS 700 1- Huber A R. joint author BORIS 700 1- Pichler Hefti Jacqueline Renée joint author BORIS 773 0- Endocrine Connections 7(10), pp. 1081-1089 2049-3614 BK010053 XK010053 XK010000 BORIS BORIS BORIS info:eu-repo/semantics/article openAccess