Hippocampal sst(1) receptors are autoreceptors and do not affect seizures in rats.

Abstract

Somatostatin-14 (SRIF-14) exerts anticonvulsive effects in several rat seizure models, generally attributed to sst(2) receptor activation. Whereas sst(1) immunoreactivity has been localized to both polymorphic interneurons and principal cells in the rat hippocampus, its potential role as an inhibitory autoreceptor or as a receptor involved in mediating anticonvulsive actions remains unknown. We showed that intrahippocampal administration of the sst(1) antagonist SRA880 (1 microM) induced a robust increase in hippocampal SST-14 levels without affecting gamma-aminobutyric acid levels in conscious rats, indicating that the sst(1) receptor acts as an inhibitory autoreceptor. SRA880 did not affect seizure severity and did not reverse the anticonvulsive action of SRIF-14 (1 microM) against pilocarpine-induced seizures, suggesting that hippocampal sst(1) receptors are not involved in the anticonvulsive effects of SRIF-14.

• Authors: Dimitri De Bundel, Najat Aourz, Foteini Kiagiadaki, Ralph Clinckers, Daniel Hoyer, Andreas Kastellakis, Yvette Michotte, Kyriaki Thermos, Ilse Smolders
• Journal: Neuroreport (Neuroreport) Vol. 21 Issue 4 Pg. 254-8 (Mar 10 2010) ISSN: 1473-558X [Electronic] England
• PMID: 20134357 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 1,2,3,4,4a,5,10,10a-octahydro-6-methoxy-1-methylbenz(g)quinoline-3-carboxylic acid 4-(4-nitrophenyl)piperazine amide
• Autoreceptors
• Muscarinic Agonists
• Piperazines
• Quinolines
• Receptors, Somatostatin
• somatostatin receptor type 1
• Pilocarpine
• Somatostatin
• gamma-Aminobutyric Acid

Topics

• Animals
• Autoreceptors (metabolism)
• Chromatography, Liquid
• Hippocampus (chemistry, drug effects, metabolism)
• Male
• Microdialysis (methods)
• Microinjections (methods)
• Muscarinic Agonists
• Pilocarpine
• Piperazines (administration & dosage, pharmacology)
• Quinolines (administration & dosage, pharmacology)
• Rats
• Rats, Wistar
• Receptors, Somatostatin (agonists, metabolism)
• Seizures (chemically induced, metabolism)
• Somatostatin (drug effects, metabolism)
• gamma-Aminobutyric Acid (metabolism)