Tag: hypothalamic 5-hydroxytryptamine receptors

Postviral fatigue syndrome

Comment on: Possible upregulation of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome. [BMJ. 1992]

 

EDITOR,-A M 0 Bakheit and colleagues suggest that the buspirone challenge test may be useful in distinguishing between a “primary depressive illness” and the postviral fatigue syndrome. It is difficult to assess the truth of this from the data presented in their paper. To know the usefulness of this test the numbers of controls and patients scored above or below an appropriately chosen cut off point of serum prolactin concentration needs to be known. Unfortunately, the authors present the prolactin concentrations as mean values. If the aim of the test is to exclude major depression then a cut off which produces few false negative results should be chosen. Were the high mean values in the postviral fatigue group due to one or two extreme outliers? It is noteworthy that the standard deviations in the patients were much higher in the controls at baseline assessment. Why was this?

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1882426/pdf/bmj00077-0052c.pdf

 

Source: Hatcher S. Postviral fatigue syndrome. BMJ. 1992 Jun 13;304(6841):1566; author reply 1567. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1882426/

 

Postviral fatigue syndrome

Comment on: Possible upregulation of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome. [BMJ. 1992]

 

EDITOR,-A M 0 Bakheit and colleagues report an enhanced prolactin response to buspirone in patients with postviral fatigue syndrome and suggest this may be due to upregulation of hypothalamic 5-hydroxytryptamine receptors. They fail to mention the considerable evidence indicating that the drug is a moderately potent dopamine antagonist, a pharmacological action which suggests an alternative explanation for their data.

They administered a single 60 mg dose of buspirone-in excess of the daily maximum of 45 mg recommended by the British National Formulary-so antidopaminergic effects may well have been significant in their studies. The fact that the prolactin releasing effect of buspirone can be blocked by the drug metergoline does not prove 5-hydroxytryptamine receptor specificity. Indeed, metergoline is used commonly as an alternative dopamine agonist to bromocriptine in managing hyperprolactinaemia. Thus enhanced prolactin release after buspirone in postviral fatigue syndrome may reflect, at least in part, inhibition of increased hypothalamic dopaminergic tone on the  It would be interesting to study the same groups of patients using a specific D2 dopamine antagonist (such as domperidone) to see whether this is the case.

You can read the rest of this comment here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1882431/pdf/bmj00077-0052d.pdf

 

Source: Bevan JS. Postviral fatigue syndrome. BMJ. 1992 Jun 13;304(6841):1566; author reply 1567. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1882431/

 

Possible upregulation of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome

Abstract:

OBJECTIVE: To study the dynamic function of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome.

DESIGN: Prospective comparison of patients with postviral fatigue syndrome with two control groups.

SETTING: Department of neurology, University of Glasgow, Southern General Hospital; department of psychiatry, St James’s Hospital, Dublin.

SUBJECTS: 15 patients with postviral fatigue syndrome, 13 age and sex matched healthy subjects, and 13 patients with primary depression.

MAIN OUTCOME MEASURES: Serum prolactin concentrations before and one, two, and three hours after administration of buspirone.

RESULTS: Because of the effects of sex hormones on prolactin secretion data for men and women were analysed separately. There was no significant difference in baseline prolactin concentrations between patients with postviral fatigue syndrome and healthy subjects or those with primary depression. However, the percentage difference between peak and baseline values was significantly higher in patients with postviral fatigue syndrome than the control groups (one way analysis of variance: women, p = 0.003; men, p = 0.004).

CONCLUSIONS: The results suggest upregulation of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome but not in those with primary depression. The buspirone challenge test may therefore be useful in distinguishing these two conditions. Larger studies are required to explore the potential value of drugs acting on central 5-hydroxytryptamine receptors in the treatment of patients with the postviral fatigue syndrome.

Comment in:

Postviral fatigue syndrome. [BMJ. 1992]

Postviral fatigue syndrome. [BMJ. 1992]

Postviral fatigue syndrome. [BMJ. 1992]

Postviral fatigue syndrome. [BMJ. 1992]

 

Source: Bakheit AM, Behan PO, Dinan TG, Gray CE, O’Keane V. Possible upregulation of hypothalamic 5-hydroxytryptamine receptors in patients with postviral fatigue syndrome.BMJ. 1992 Apr 18;304(6833):1010-2. http://www.ncbi.nlm.nih.gov/pubmed/1586780

Note: You can read the full article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1881733/