Tag: d-fenfluramine

Contrasting neuroendocrine responses in depression and chronic fatigue syndrome

Abstract:

Hypothalamic-pituitary-adrenal (HPA) axis and central 5-HT function were compared in chronic fatigue syndrome (CFS), depression and healthy states. 10 patients with CFS and 15 patients with major depression were matched for age, weight, sex and menstrual cycle with 25 healthy controls.

Baseline-circulating cortisol levels were highest in the depressed, lowest in the CFS and intermediate between the two in the control group (P = 0.01). Prolactin responses to the selective 5-HT-releasing agent d-fenfluramine were lowest in the depressed, highest in the CFS and intermediate between both in the healthy group (P = 0.01). Matched pair analysis confirmed higher prolactin responses in CFS patients than controls (P = 0.05) and lower responses in depressed patients than controls (P = 0.003). There were strong inverse correlations between prolactin and cortisol responses and baseline cortisol values.

These data confirm that depression is associated with hypercotisolaemia and reduced central 5-HT neurotransmission and suggest that CFS may be associated with hypocortisolaemia and increased 5-HT function. The opposing responses in CFS and depression may be related to reversed patterns of behavioural dysfunction seen in these conditions. These findings attest to biological distinctions between these disorders.

 

Source: Cleare AJ, Bearn J, Allain T, McGregor A, Wessely S, Murray RM, O’Keane V. Contrasting neuroendocrine responses in depression and chronic fatigue syndrome. J Affect Disord. 1995 Aug 18;34(4):283-9. http://www.ncbi.nlm.nih.gov/pubmed/8550954

 

Neuroendocrine assessment of serotonin (5-HT) function in chronic fatigue syndrome

Abstract:

Prolactin and cortisol responses to dl-fenfluramine challenge were examined in 11 patients with chronic fatigue syndrome and in 11 healthy controls who were age and gender matched. After obtaining two baseline samples, each subject was given 60 mg of dl-fenfluramine orally and further blood samples were drawn hourly during the following five hours in order to measure prolactin and cortisol levels. There was no difference in either baseline or fenfluramine-induced hormonal responses between patients with chronic fatigue syndrome and controls. There was also no correlation between depression scores on HAM-D and hormonal responses in patients with chronic fatigue syndrome. The findings of this study do not support a role for 5-HT in chronic fatigue syndrome.

Comment in: Re: Endocrine responses to fenfluramine challenge in chronic fatigue syndrome. [Can J Psychiatry. 1996]

 

Source: Yatham LN, Morehouse RL, Chisholm BT, Haase DA, MacDonald DD, Marrie TJ. Neuroendocrine assessment of serotonin (5-HT) function in chronic fatigue syndrome. Can J Psychiatry. 1995 Mar;40(2):93-6. http://www.ncbi.nlm.nih.gov/pubmed/7788624

 

Neuroendocrine responses to d-fenfluramine and insulin-induced hypoglycemia in chronic fatigue syndrome

Abstract:

Chronic fatigue syndrome (CFS) is a disorder characterized by severe physical and mental fatigue and fatiguability of central rather than peripheral origin.

We hypothesized that CFS is mediated by changes in hypothalamopituitary function and so measured the adrenocorticotrophic hormone (ACTH), cortisol, growth hormone, and prolactin responses to insulin-induced hypoglycemia, and the ACTH, cortisol, and prolactin responses to serotoninergic stimulation with dexfenfluramine in nondepressed CFS patients and normal controls.

We have shown attenuated prolactin responses to hypoglycemia in CFS. There was also a greater ACTH response and higher peak ACTH concentrations (36.44 +/- 4.45 versus 25.60 +/- 2.78 pg ml), whereas cortisol responses did not differ, findings that are compatible with impaired adrenal cortical function.

This study provided evidence for both pituitary and adrenal cortical impairment in CFS and further studies are merited to both confirm and determine more precisely their neurobiological basis so that rational treatments can be evolved.

 

Source: Bearn J, Allain T, Coskeran P, Munro N, Butler J, McGregor A, Wessely S. Neuroendocrine responses to d-fenfluramine and insulin-induced hypoglycemia in chronic fatigue syndrome. Biol Psychiatry. 1995 Feb 15;37(4):245-52. http://www.ncbi.nlm.nih.gov/pubmed/7711161