Antidepressants reverse the olfactory bulbectomy-induced decreases in splenic peripheral-type benzodiazepine receptors in rats.
The present study investigated the effects of 21-day administration of clorgyline (1 mg/kg/day), desipramine (10 mg/kg/day) or paroxetine (10 mg/kg/day) on peripheral-type benzodiazepine receptors in rat peripheral tissues following bilateral olfactory bulbectomy. Thymus and spleen weights decreased as a result of bulbectomy. Subsequent antidepressant drug administration had no further effects on the weights of thymus glands but increased those of spleens. In thymus glands, higher densities of peripheral-type benzodiazepine receptors were observed in medulla than in cortex; no significant variations were observed following bulbectomy or antidepressant drug administration. In spleen, higher densities were observed in white pulp than in red pulp. The bulbectomy-induced decreases in binding densities observed in both regions were reversed following administration of antidepressants. Adrenal peripheral-type benzodiazepine receptors were not altered by bulbectomy or subsequent treatment with clorgyline or desipramine while paroxetine upregulated these receptors. No changes in kidney peripheral-type benzodiazepine receptors were observed. The present study confirms that cell lines of the rat immune system possess high densities of peripheral-type benzodiazepine receptor binding sites and further support the contention that, following olfactory bulbectomy, rats may present an antidepressant-reversible immunitary dysfunction.
Dennis
T
T
Department of Psychiatry, McGill University, Montreal, Quebec, Canada.
Beauchemin
V
V
Lavoie
N
N
D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D003010:Clorgyline / Q000494:pharmacology; D003891:Desipramine / Q000494:pharmacology; D007108:Immune Tolerance; D007546:Isoquinolines / Q000378:metabolism; D008297:Male; D009830:Olfactory Bulb / Q000502:physiology* / Q000601:surgery; D009929:Organ Size / Q000187:drug effects; D017374:Paroxetine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000032:analysis / Q000187:drug effects*; D011985:Receptors, Serotonin / Q000032:analysis; D013154:Spleen / Q000737:chemistry / Q000187:drug effects*; D013950:Thymus Gland / Q000187:drug effects
D000928:Antidepressive Agents; D007546:Isoquinolines; D011963:Receptors, GABA-A; D011985:Receptors, Serotonin; D017374:Paroxetine; D003010:Clorgyline; D003891:Desipramine; C037850:PK 11195