Alterations of serotonin receptor binding in the hypothalamus following acute denervation

• Published in: Brain research Vol. 601; no. 1; pp. 349 - 352
• Main Authors: Frankfurt, Maya, Mendelson, Scott D., McKittrick, Christina R., McEwen, Bruce S.
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 22.01.1993; Amsterdam Elsevier; New York, NY
• Subjects: 5,7-Dihydroxytryptamine; 5,7-Dihydroxytryptamine - administration & dosage; 5,7-Dihydroxytryptamine - pharmacology; Animals; Autoradiography; Axons - drug effects; Biological and medical sciences; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Denervation; Dorsomedial Hypothalamic Nucleus - metabolism; Fundamental and applied biological sciences. Psychology; Hippocampus - physiology; Hypothalamic Area, Lateral; Hypothalamus; Hypothalamus - metabolism; Injections; Ligands; Male; Paroxetine - metabolism; Rats; Receptor; Receptors, Serotonin - metabolism; Serotonin; Ventromedial Hypothalamic Nucleus - metabolism; Vertebrates: nervous system and sense organs; Autoradiography; Hypothalamus; Serotonin; 5,7-Dihydroxytryptamine; Receptor; Vertebrata; Mammalia; Rat; Rodentia; Central nervous system; Brain (vertebrata); Quantitative analysis; Denervation; S1 receptor
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/0006-8993(93)91735-B

Quantitative autoradiography was used to determine the effect of acute serotonergic denervation with 5,7-dihydroxytryptamine (5,7-DHT) on serotonin 5HT 1a and 5-HT 1b receptors in male rats. Seven days after intrahypothalamic 5,7-DHT injection there was a significant increase in the density of 5HT 1a receptors in the ventromedial and dorsomedial hypothalamic nuclei (VMN and DMN) of male rats. In adjacent sections, 5-HT 1b receptors were significantly increased only in the VMN. No changes in receptor density were observed in the lateral hypothalamic area or hippocampus even though binding of [ 3H]paroxetine, which labels the presynaptic transporter site, was significantly decreased in all evaluated brain regions in 5,7-DHT-treated animals. In addition to demonstrating that 5-HT 1a and 5-HT 1b receptors are differentially regulated in different brain areas, these results show that in the brain regions examined both 5-HT 1a and 5-HT 1b receptors are primarily post-synaptic.