Chronic chlorimipramine does not reverse the reduction of cerebrospinal fluid Met-enkephalin-like immunoreactivity in chronic-pain patients.
Chronic-pain patients were treated for 10 days with chlorimipramine (100 mg i.v. daily), and their plasma levels of the drug and cerebrospinal fluid (CSF) levels of Met-enkephalin-like material (MELM) were measured for a comparison with those found in untreated chronic-pain patients and in control subjects. Pain relief in chlorimipramine-treated patients was apparently not associated with pronounced changes in the activity of enkephalinergic systems since the mean CSF levels of MELM were reduced to the same extent in treated (-49%) and untreated (-45%) pain patients as compared with controls. However, subtle chlorimipramine-induced alterations likely occurred as revealed by the simultaneous measurement of the CSF levels of 5-hydroxyindoleacetic acid (5-HIAA) in the same patients. Indeed, a positive correlation (r = 0.667) was found between CSF 5-HIAA and MELM levels in control subjects, whereas a negative correlation (r = 0.691) between these two parameters was detected in chlorimipramine-treated patients. These data suggest that chlorimipramine alters probable functional serotonin-enkephalin interactions in pain patients.
Bourgoin
S
S
INSERM U. 288, Neurobiologie Cellulaire et Fonctionnelle, Faculté de Médecine, Paris, France.
Cesselin
F
F
Gozlan
H
H
Fattaccini
C M
CM
Tran
M A
MA
Montastruc
J L
JL
Rascol
A
A
Hamon
M
M
D000328:Adult; D000368:Aged; D002908:Chronic Disease; D002997:Clomipramine / Q000097:blood / Q000494:pharmacology / Q000627:therapeutic use*; D004744:Enkephalin, Methionine / Q000031:analogs & derivatives* / Q000134:cerebrospinal fluid / Q000276:immunology; D004745:Enkephalins / Q000378:metabolism / Q000502:physiology; D005260:Female; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000134:cerebrospinal fluid / Q000188:drug therapy* / Q000503:physiopathology; D011863:Radioimmunoassay; D012701:Serotonin / Q000378:metabolism / Q000502:physiology
D004745:Enkephalins; C024693:enkephalin-Met, like substances; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D004744:Enkephalin, Methionine; D002997:Clomipramine