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Featured researches published by R.M. Frieboes.


Psychoneuroendocrinology | 2003

On the role of menopause for sleep-endocrine alterations associated with major depression

I.A. Antonijevic; H. Murck; R.M. Frieboes; Manfred Uhr; A. Steiger

Aging and menopause are associated with alterations of the sleep EEG, while age-related changes of the hypothalamo-pituitary-adrenal (HPA) axis remain controversial. Major depression is also associated with typical sleep-endocrine changes, including enhanced activity of the HPA axis, while an influence of age and gender on these alterations is less clear. To test the hypothesis that after menopause sleep-endocrine alterations associated with major depression are accentuated, we examined the sleep EEG and nocturnal hormone secretion (ACTH, cortisol, GH, estradiol, LH, FSH, and leptin) in 16 drug-free female patients, mostly with the first episode of a major depressive disorder (seven pre- and nine postmenopausal subjects) and 19 female controls (10 subjects in the early follicular phase and nine postmenopausal subjects). Nocturnal cortisol secretion was increased in postmenopausal patients with depression, while a decrease was noted in postmenopausal controls. Sleep alterations typically associated with depression, namely a reduction in sleep continuity and slow wave sleep (SWS) and an increase in REM density, were prominent in post- but not in premenopausal patients. An inverse correlation was noted between the decline in SWS and sleep continuity and FSH secretion in patients with depression, suggesting a role of menopause for these sleep-endocrine alterations typically associated with major depression. In contrast, in premenopausal patients we noted primarily a shift in SWS and delta-EEG activity from the first to the second non-REM period, which was not related to age or hormone secretion. Though the relatively small number of subjects per group precludes a definitive conclusion, our data open up the possibility that the sleep-endocrine changes typically associated with major depression are most prominent in postmenopausal patients. Whether the predominant alteration of the distribution of SWS and delta EEG activity in younger patients with a first episode of major depression has a predictive value for the future course of the disease remains to be investigated.


Journal of Neuroendocrinology | 2001

Effects of Growth Hormone‐Releasing Peptide‐6 on the Nocturnal Secretion of GH, ACTH and Cortisol and on the Sleep EEG in Man: Role of Routes of Administration

R.M. Frieboes; H. Murck; I.A. Antonijevic; A. Steiger

After repeated intravenous (i.v.) boluses of growth hormone‐releasing peptide‐6 (GHRP‐6) we found recently increases of growth hormone (GH), corticotropin (ACTH) and cortisol levels and of the amount of stage 2 sleep. In clinical use, oral (p.o.), intranasal (i.n.) and sublingual (s.l.) routes of administration have advantages over i.v. administration. We compared the sleep‐endocrine effects of 300 μg/kg of body weight (b.w.) GHRP‐6 in enteric‐coated capsules given p.o. at 21.00 h and of 30 μg/kg GHRP‐6 i.n. or 30 μg/kg GHRP‐6 sl. given at 22.45 h in normal young male controls with placebo conditions. After GHRP‐6 p.o. secretion of GH, ACTH and cortisol remained unchanged. The only effect of GHRP‐6 s.l. was a trend toward an increase in GH in the first half of the night. GHRP‐6 i.n. prompted a significant increase in GH concentration during the total night and a trend toward an increase in ACTH secretion during the first half of the night, whereas cortisol secretion remained unchanged. Furthermore, after GHRP‐6 i.n., sleep stage 2 increased in the second half of the night by trend, and spectral analysis of total night non‐rapid eye movement (REM) sleep revealed a decrease of delta power by trend. In contrast sleep stage 2 decreased during the second half of the night after GHRP‐6 p.o. Our data demonstrate that GHRP‐6 is capable of modulating GH and ACTH secretion as well as sleep. However, the effects depend upon dosage, duration and route of administration.


Archive | 1996

Vasoaktives Intestinales Peptid (VIP) verlangsamt Non-REM/REM-Zyklen und moduliert die nachtliche Hormonsekretion des Menschen

H. Murck; Jürgen Guldner; M. Colla; R.M. Frieboes; Thomas Schier; Klaus Wiedemann; Florian Holsboer; A. Steiger

Intracerebroventrikulare Applikation von VIP fuhrte zu einer signifikanten Steigerung von REM-Schlaf in Ratten [6, 9], Kaninchen [7] und Katzen [3]. VIP stimuliert daneben die Wachstumshormon-Sekretion bei der Ratte [2] sowie der Prolaktinsekretion sowohl bei der Ratte [4] als auch beim Menschen [5, 8]. Auserdem gibt es Hinweise, das VIP eine Rolle bei der Regulation des circadianen Rhythmus uber einen Einflus auf den Nucleus suprachiasmaticus ausubt [1]. Wir untersuchten den Effekt von stundlichen pulsatilen peripheren Applikationen zwischen 22.00 und 1.00 Uhr von 4 × 10 µg VIP (n = 7) und 4 × 50 µg VIP (n = 10) auf den Schlaf und auf die nachtliche endokrine Aktivitat bei mannlichen Kontrollpersonen (20–30 Jahre alt) gegenuber Placebo. Nach Applikation von 4 × 10 µg VIP sank die Prolaktinkonzentration signifikant (Area under the curve AUC: 4651 ± 542 ng/ml x min nach VIP vs. 6293 + 856 ng/ml x min nach Placebo, im Zeitraum von 22.00 bis 7.00 Uhr, p < 0,05), wohingegen das Schlaf-EEG keine Veranderungen aufwies. Nach Gabe von 4 × 50 µg VIP wurde ein signifikanter Anstieg von Prolaktin beobachtet (22.00 bis 3.00 Uhr: 3526 ± 325 ng /ml x min vs. 2766 ± 313 ng/ml x min, p < 0, 01). Nach 4 × 50 µg VIP war der Cortisolnadir signifikant vorverlagert (62 ± 27 min unter VIP vs. 146 ± 19 min unter Placebo, p < 0,01, Zeit nach „Licht aus“). Zwischen 0.20 und 4.40 Uhr fand sich in Folge davon eine signifikante Erhohung der Cortisolkonzentration (11965 ± 1939 ng/ml x min vs. 7747 ± 1136 ng/ml x min, p < 0, 05).


Archive | 1996

Neuropsychologische Defizite und psychische Störungen nach hypoxischer Hirnschädigung

R.M. Frieboes; Ulrich Müller; D. Y. von Cramon

Im Zuge neuer intensivmedizinischer Erkenntnisse uberlebt eine grose Zahl von Patienten mit hypoxiebedingter Schadigung des Organismus das ursachliche Ereignis. In der retrospektiven Auswertung wird ein Profil neuropsychologischer Defizite einer Patientengruppe mit mittelschwerer hypoxamischer Hirnschadigung unterschiedlicher Genese beschrieben.


Archive | 1996

Diagnose und Therapie emotionaler Instabilität nach Hirninfarkt

Ulrich Müller; R.M. Frieboes; D. von Cramon

Bei der Exploration von Patienten mit Hirninfarkten kommt es haufig zu einem der Situation unangemessenen Weinen. Diese „special tendency to induce weeping“ wurde bereits 1872 von Charles Darwin in seiner Monographie uber The Expression of Emotions in Man and Animal erwahnt. Das klinische Phanomen hat im Laufe der Jahre viele Namen erhalten, die entweder auf bestimmten Vorstellungen zur Pathoatiologie beruhen, wie pseudobulbarer Affekt, Zwangsweinen, Affektinkontinenz, oder eher deskriptiv sind, wie die von Poeck vorgeschlagene Unterscheidung von Affektlabilitat und pathologischem Weinen [12]. In Ubereinstimmung mit den terminologischen Uberlegungen von Allman [1] bevorzugen wir die Bezeichnung emotionalism, was wir als „emotionale Instabilitat“ ubersetzt haben.


Psychopharmacology | 2001

Distinct temporal pattern of the effects of the combined serotonin-reuptake inhibitor and 5-HT1A agonist EMD 68843 on the sleep EEG in healthy men.

H. Murck; R.M. Frieboes; I.A. Antonijevic; A. Steiger


Pharmacopsychiatry | 1997

Longtime administration of growth hormone-releasing hormone (GHRH) does not restore the reduced efficiency of GHRH on sleep endocrine activity in 2 old-aged subjects - a preliminary study

H. Murck; R.M. Frieboes; T. Schier; A. Steiger


Biological Psychiatry | 1997

Opposite effects of growth hormone-releasing hormone and somatostatin on the sleep EEG in elderly controls

A. Steiger; R.M. Frieboes; J. Guldner; H. Murck; T. Schier


Biological Psychiatry | 1997

Effects of PACAP on sleep EEG and nocturnal hormone secretion in men

I.A. Antonijevic; H. Murck; R.M. Frieboes; S. Bohlhalter; T. Schier; A. Steiger


Biological Psychiatry | 1997

Blunted nocturnal cortisol release after GHRH in male, but not in female patients with depression

A. Steiger; I.A. Antonijevic; R.M. Frieboes; H. Murck

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