Project description:Feeding is an important activity for all animals providing nutrients essential for survival and reproduction. Not surprisingly, learning plays a critical role in feeding behavior through the establishment and strengthening of food preferences and aversions. That is, the integration of taste and post ingestive visceral signals in the brain results in memorial representations about the consequences associated with ingesting a particular food. For example, when ingestion of a food is followed by negative gastrointestinal consequences (e.g. nausea, sickness, or vomiting), the animal develops a conditioned taste aversion (CTA), which produces a switch from acceptance to avoidance of that and any like tasting stimulus. Despite recent advances in understanding CTA responsive intracellular signaling pathways in the amygdala, little is known about any long-term regulation of target gene expression following CTA memory consolidation and retrieval. The present study utilized oligo-nucleotide microarray to understand the genes and networks involved in Conditional Taste Aversion Behavior.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes
Project description:Animals must learn through experience which foods are nutritious and should be consumed, and which are toxic and should be avoided. Enteroendocrine cells (EECs) are the principal chemosensors in the GI tract, but investigation of their role in behavior has been limited by the difficulty of selectively targeting these cells in vivo. Here we describe an intersectional genetic approach for manipulating EEC subtypes in behaving mice. We show that multiple EEC subtypes inhibit food intake but have different effects on learning. Conditioned flavor preference is driven by release of cholecystokinin whereas conditioned taste aversion is mediated by serotonin and substance P. These positive and negative valence signals are transmitted by vagal and spinal afferents, respectively. These findings establish a cellular basis for how chemosensing in the gut drives learning about food.
