Serotonin-induced increases in platelet cytosolic calcium concentration in depressed, schizophrenic, and substance abuse patients.
Exaggerated intracellular calcium responses to challenges with serotonin (5-HT) have been reported in depression. In our studies, consistent with previous reports, patients with depression exhibited an exaggerated increase in 5-HT-stimulated intracellular calcium concentration ([Ca++]i). Basal cytosolic calcium was elevated in both calcium-free and 1 mM calcium media in depressed patients. the increased responsiveness to 5-HT was seen in both conditions. Patients with schizophrenia and substance abuse did not differ from normal controls. The 5-HT response was correlated with diastolic blood pressure (r = 0.33, p = 0.02): however, this association did not fully account for the exaggerated [Ca++]i responses in the depressed group. These findings suggest that exaggerated increases in [Ca++]i in response to serotonin are a characteristic of depressed patients not shared with schizophrenic and substance abuse patients. The relationship of depression to hypertension, two conditions that share abnormalities of calcium homeostasis, warrants further study.
Konopka
L M
LM
Section on Biological Psychiatry, Hines VA Hospital, IL 60141, USA.
Cooper
R
R
Crayton
J W
JW
D000328:Adult; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D001794:Blood Pressure / Q000502:physiology; D002118:Calcium / Q000097:blood*; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism*; D003866:Depressive Disorder / Q000097:blood; D006801:Humans; D006973:Hypertension / Q000097:blood; D001523:Mental Disorders / Q000097:blood*; D012559:Schizophrenia / Q000097:blood; D012701:Serotonin / Q000494:pharmacology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D019966:Substance-Related Disorders / Q000097:blood
D017366:Serotonin Receptor Agonists; D012701:Serotonin; D002118:Calcium