Abstract
Norepinephrine (NE) was microinjected into the paraventricular nucleus (PVN), while microdialysis was used to monitor extracellular dopamine (DA) and acetylcholine (ACh) in the nucleus accumbens (NAc). The PVN is a site where exogenously administered NE can act through α2 receptors to elicit eating behavior and preference for carbohydrates. It was hypothesized that NE in the PVN acts on a behavior reinforcement system by altering the DA/ACh balance in the NAc. NE microinjections (80 nmol in 0.3 μl), which effectively elicited feeding in satiated rats in a separate test, caused a significant increase in extracellular DA (109%) and decrease in ACh (-27%) when the same animals were tested in the absence of food. In contrast when the food was available and ingested, ACh increased (51%) instead of decreasing. These results support the hypothesis that a functional link exists between the PVN and the NAc in which DA helps initiate and ACh helps stop appetitive behavior involved in the reinforcement of eating.
Original language | English (US) |
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Pages (from-to) | 667-674 |
Number of pages | 8 |
Journal | Journal of neurochemistry |
Volume | 68 |
Issue number | 2 |
DOIs | |
State | Published - Feb 1997 |
Externally published | Yes |
Keywords
- Acetylcholine
- Dopamine
- Feeding
- Hypothalamic paraventricular nucleus
- Microdialysis
- Norepinephrine
- Nucleus accumbens
- Rat
ASJC Scopus subject areas
- Biochemistry
- Cellular and Molecular Neuroscience