Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P46098 (5-HT3 receptor)
 2,290 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transcription regulatory factors are rapidly induced in brain by a wide variety of stimuli and may be important in coordinating changes in gene expression under-lying neuronal plasticity. Using in situ hybridization, we found that acute cocaine administration (20 mg/kg, intraperitoneally (i.p.)) produced a robust induction of both c-fos and egr-1 immediate early genes. Egr-1 messenger RNA induction was highest in the caudate putamen and in the shell of the nucleus accumbens. No significant induction was noticed after injection of fluoxetine, a selective inhibitor of serotonin uptake. Cocaine-induced egr-1 and c-fos expression was substantially reduced in the brain areas from rats in which the serotonergic projections were lesioned by injection of the neurotoxin 5,7-dihydroxytryptamine and in rats that have been injected with tropisetron, an antagonist of the 5-hydroxytryptamine (5-HT3) receptor. Conversely, the 5-HT3 receptor agonist 2-methylserotonin induced the expression of these early genes in structures including the caudate putamen and nucleus accumbens.
 ...
PMID:The serotonergic system modulates the cocaine-induced expression of the immediate early genes egr-1 and c-fos in rat brain. 966 60

We examined c-fos expression in specific brain nuclei in response to gastric distension and investigated whether 5-HT released from enterochromaffin (EC) cells was involved in this response. The role of 5-HT3 receptors in this mechanism was also addressed. Release of 5-HT was examined in an ex vivo-perfused stomach model, whereas c-fos expression in brain nuclei induced by gastric distension was examined in a freely moving conscious rat model. Physiological levels of gastric distension stimulated the vascular release of 5-HT more than luminal release of 5-HT, and induced c-fos expression in the nucleus of the solitary tract (NTS), area postrema (AP), paraventricular nucleus (PVN), and supraoptic nucleus (SON). The c-fos expression in all these brain nuclei was blocked by truncal vagotomy as well as by perivagal capsaicin treatment, suggesting that vagal afferent pathways may mediate this response. Intravenous injection of 5-HT3 receptor antagonist granisetron blocked c-fos expression in all brain nuclei examined, although intracerebroventricular injection of granisetron had no effect, suggesting that 5-HT released from the stomach may activate 5-HT3 receptors located in the peripheral vagal afferent nerve terminals and then induce brain c-fos expression. c-fos Positive cells in the NTS were labeled with retrograde tracer fluorogold injected in the PVN, suggesting that neurons in the NTS activated by gastric distension project axons to the PVN. The present results suggest that gastric distension stimulates 5-HT release from the EC cells and the released 5-HT may activate 5-HT3 receptors located on the vagal afferent nerve terminals in the gastric wall leading to neuron activation in the NTS and AP and subsequent activation of neurons in the PVN and SON.
 ...
PMID:Gastric distension-induced release of 5-HT stimulates c-fos expression in specific brain nuclei via 5-HT3 receptors in conscious rats. 1468 79