Quantitative autoradiographic changes in 5-[3H]HT-labeled 5-HT1 serotonin receptors in discrete regions of brain in the rat model of persistent dyskinesias induced by iminodipropionitrile (IDPN).
Chronic injections of iminodipropionitrile (IDPN) to rat cause a persistent motor hyperactivity, lateral and vertical sustained twisting movement of the neck, random circling and increased startle response. These abnormalities are similar to those observed after the acute administration of serotonin (5-HT) agonists in rodents. Significant changes in 5-HT concentration and in 5-HT2 receptor density in several motor-related brain regions have been observed in IDPN-treated rats. The present quantitative autoradiographic study was undertaken to assess the possibility that IDPN may also affect 5-HT1 receptors in rat brain. IDPN caused significant increases of 5-[3H]HT binding in the oriens and pyramidal layers of the CA3 field of hippocampus. In contrast, there were significant decreases of 5-[3H]HT binding in the frontal and cingulate cortices, the olfactory tubercle, the ventromedial aspect of the caudate-putamen, the nucleus accumbens, the superior colliculus, and the lateral septal nuclei. These results provide further evidence for the involvement of the 5-HT system in the development of the IDPN-induced dyskinetic syndrome.
Przedborski
S
S
Neurological Institute, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Wright
M
M
Fahn
S
S
Cadet
J L
JL
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism*; D004195:Disease Models, Animal; D004409:Dyskinesia, Drug-Induced / Q000378:metabolism*; D008297:Male; D009570:Nitriles; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D014316:Tritium
D009570:Nitriles; D011985:Receptors, Serotonin; D014316:Tritium; D012701:Serotonin; C008110:3,3'-iminodipropionitrile