Changes in Platelet Alpha-2-Adrenoceptors in Fibromyalgia: Effects of Treatment with Antidepressants

Abstract

The aim of this study was to determine platelet α₂-adrenergic receptor (α₂-AR) binding sites in fibromyalgia both before and after treatment with sertraline or placebo. The maximum number of binding sites (B_max) and their affinity (K_d) for [³H]rauwolscine, a selective α₂-AR antagonist, were measured in 13 normal volunteers and 22 fibromyalgia patients. Severity of illness was evaluated by means of the Hamilton Depression Rating Scale (HDRS) and dolorimetric assessments of tenderness at tender points. Fibromyalgia patients had repeated measurements of [³H]rauwolscine binding characteristics both before and after subchronic treatment with sertraline or placebo for 12 weeks. [³H]rauwolscine binding K_d values were significantly higher in fibromyalgia patients than in normal volunteers. There were significant inverse correlations between [³H]rauwolscine binding K_d values and duration of illness, age and lower energy. Significantly higher [³H]rauwolscine binding K_d values were found in fibromyalgia patients in an early phase of illness (<3 years) than in fibromyalgia patients with a protracted illness (>3 years). Repeated administration of sertraline had no significant effects on [³H]rauwolscine binding B_max or K_d values. The results suggest that fibromyalgia and, in particular, fibromyalgia in an early phase of illness, is accompanied by lowered affinity of platelet α₂-ARs.

Urinary electrophoretic profiles from chronic fatigue syndrome and chronic fatigue syndrome/fibromyalgia patients: a pilot study for achieving their normalization

“…They may reflect differences in plasma concentrations; filtration (autonomic control of renal glomerular blood flow); renal tubule peptidases, reabsorption or secretion; or even bladder epithelial origins. If CFS represents a systemic illness with proteomic changes in multiple cell types (e.g., platelets and muscle [39][40][41][42][43][44]) then the tissues immediately responsible for the analytes present in the urine or their chemical modification may offer novel clues into disease pathophysiology.…”

Antidepressants as long-acting local anesthetics

“…25 Interestingly, it has been shown that ␣ 2 -adrenoceptors have lower affinity for agonist in patients with fibromyalgia than in controls. 26 Changes in this signaling system have also been observed in major depression. 27 …”