Acute and chronic treatments with citalopram lower somatostatin levels in rat brain striatum through different mechanisms

Elena Prosperini, Massimo Rizzi, Fabio Fumagalli, Gianluca Tarizzo, Rosario Samanin, Caterina Bendotti

Research output: Contribution to journalArticlepeer-review

Abstract

The suggestion that somatostatin is involved in the pathophysiology of obsessive-compulsive disorder and the evidence that selective serotonin reuptake inhibitors show significant antiobsessional effect prompted us to examine the effect of citalopram, a selective and potent serotonin reuptake inhibitor, on the somatostatinergic system in different brain regions of the rat. A single intraperitoneal injection of 10 mg/kg citalopram significantly reduced somatostatin levels in the striatum and nucleus accumbens after 4 but not 1, 8, or 24 h. No changes were found in hippocampus. In addition, we found that the K+-evoked overflow of somatostatin-like immunoreactivity from striatal slices was significantly increased 1 h after a single injection of citalopram and was still higher, although not significantly, 4 h after the drug injection. Levels of preprosomatostatin mRNA were unchanged in striatum and accumbens 1 and 4 h after a single drug administration. In rats treated with citalopram (10 mg/kg i.p.) twice daily for 14 days, the levels of somatostatin and its mRNA were significantly decreased in the striatum but not in other brain regions 24 h after the last dose. No change was found in the basal or K+-evoked overflow of somatostatin-like immunoreactivity at 1, 4, and 24 h after the last drug injection. These results suggest that acute and chronic treatment with citalopram reduces somatostatin levels in striatum by different mechanisms. Whereas a single dose of the drug reduces somatostatin levels by increasing the release of the peptide, repeated drug treatment reduces the biosynthesis of somatostatin.

Original languageEnglish
Pages (from-to)206-213
Number of pages8
JournalJournal of Neurochemistry
Volume69
Issue number1
Publication statusPublished - Jul 1997

Keywords

  • 5-Hydroxytryptamine uptake inhibitors
  • Basal ganglia
  • Citalopram
  • Obsessive- compulsive disorder
  • Somatostatin

ASJC Scopus subject areas

  • Biochemistry
  • Cellular and Molecular Neuroscience

Fingerprint Dive into the research topics of 'Acute and chronic treatments with citalopram lower somatostatin levels in rat brain striatum through different mechanisms'. Together they form a unique fingerprint.

Cite this