Biomedical subjects

Rita M Condren

Publications and source records attributed to Rita M Condren.

5 recordsLinked to original sources

PubMed2003

Platelet surface glycoprotein expression in post-stroke depression: a preliminary study.

Depression is a significant risk factor for and consequence of both cardiovascular disease and stroke. The pathophysiological processes underlying this association are poorly understood. This study utilised a technique for measurement of whole blood platelet surface glycoproteins involved in early adhesion and aggregation in sample populations of patients with depression and stroke, and healthy controls. We analysed the platelet surface glycoproteins GPIb and GPIIbIIIa using flow cytometry in eight depressed subjects (Hamilton depression score >17), 14 post-stroke subjects (seven depressed and seven non-depressed), and in eight healthy control subjects. The number of GPIb receptors was significantly increased in subjects with depression and in post-stroke subjects compared to control subjects. The number of GPIb receptors from post-stroke subjects was not significantly different from that of depressed subjects. There were no differences between any groups in measures of GPIIbIIIa receptor numbers. No additive effect of co-morbid depression on the surface expression level of either marker could be detected in the post-stroke subjects. Platelet dysfunction may be involved in the pathophysiological process underlying the association between depression and cerebrovascular disease.

Adult↗

PubMed2003

A preliminary study of baclofen-induced growth hormone release in generalised social phobia.

OBJECTIVE: The authors sought to examine central GABA(B) receptor responses in patients with generalised social phobia using the growth hormone (GH) response to baclofen. METHOD: Baclofen 20 mg was administered to 15 patients and 15 healthy matched controls and plasma growth hormone was monitored over a 3 h period. RESULTS: The GH response in patients was significantly reduced in comparison to that of controls when calculated as both area under the curve (AUC) and delta (Delta) response. CONCLUSIONS: The results suggest an abnormality of central GABA(B) receptor function in this disorder.

Adult↗

PubMed2002

A preliminary study of dopamine-mediated prolactin inhibition in generalised social phobia.

The biology of social phobia has been little studied, but a possible role for dopamine has been implicated in this disorder. The aim of this study was to examine central dopaminergic function in patients with generalised social phobia using the prolactin response to quinagolide, a dopamine D2 receptor agonist, and to compare responses with those of normal controls. The study included 14 patients with moderate or severe generalised social phobia and 14 healthy age- and gender-matched comparison subjects. Quinagolide (0.5 mg) was administered orally and prolactin responses were measured over 4 h. There was no significant difference between prolactin responses in patients and healthy controls, nor was there a correlation between prolactin response and age, sex, or severity of illness. This would suggest that tuberoinfundibular dopamine D2 receptor sensitivity is normal in this disorder.

Adult↗

PubMed2002

Depression is associated with an increase in the expression of the platelet adhesion receptor glycoprotein Ib.

There is a significant association between cardiovascular disease and depression. Previous studies have documented changes in platelets in depression. It is unknown if depression causes functional changes in platelet surface receptors. Therefore, we analyzed (1) the surface expression of glycoprotein (GP)Ib and the integrin receptor alpha(IIb)beta(IIIa), receptors involved in platelet adhesion and aggregation, (2) CD62 (P-selectin) and CD63, integral granule proteins translocated during platelet activation, (3) platelet aggregation in response to ADP and (4) plasma levels of glycocalicin and von Willebrand factor (vWF), in depressed patients compared to healthy volunteers. Fifteen depressed patients with a Hamilton depression score of at least 22 and fifteen control subjects were studied. Platelets were assessed for surface expression levels of GPIb, alpha(IIb)beta(IIIa), CD62 and CD63 by flow cytometry. Genomic DNA was isolated to investigate a recently described polymorphism in the 5' untranslated region of the GPIbalpha gene. The number of GPIb receptors was significantly increased on the surface of platelets from patients with depression compared to control subjects. Surface expression of CD62 was also significantly increased in the depressed patients versus control subjects. There was no significant difference between depressed patients and healthy volunteers in the surface expression of alpha(IIb)beta(IIIa) or CD63, or in glycocalicin or vWF plasma concentration, or ADP-induced aggregation. There was no difference in allele frequency of the Kozak region polymorphism of the GPIbalpha gene, which can affect GPIb expression. The results of this study demonstrate that the number of GPIb receptors on platelets are increased in depression and suggest a novel risk factor for thrombosis in patients with depression.

Adult↗

PubMed2002

A preliminary study of buspirone stimulated prolactin release in generalised social phobia: evidence for enhanced serotonergic responsivity?

Serotonergic dysfunction has been postulated to play a role in the aetiology of social phobia. Buspirone, which is a partial agonist at 5HT1A receptors, increases prolactin release and may be used as a probe to examine serotonergic responses, dysfunction of which may be relevant to the pathophysiology of social phobia. We compared buspirone stimulated prolactin release in 14 patients with generalised social phobia and 14 healthy controls. Buspirone 30 mg was administered orally and prolactin release over 180 min was monitored. Overall, patients with generalised social phobia had greater prolactin release in response to buspirone challenge than healthy comparison subjects. There was no correlation between prolactin response and measures of severity of social phobia. Patients with generalised social phobia had enhanced central serotonergic responses, an abnormality shared with some other anxiety disorders and which may be of aetiological significance.

Adult↗