Numerous peripheral and hypothalamic peptides control food intake. Among these signals are orexin, an orexigenic molecule released into the olfactory bulb by centrifugal hypothalamic fibres and leptin, an anorexigenic molecule that is released peripherally and can pass through the blood-brain barrier. In the present study, we injected either orexin or leptin, intracerebroventricularly, and their effect on olfactory performance was evaluated in two groups of rats, using a behavioral paradigm based on conditioned olfactory aversion. Rats were made aversive to water odorized with isoamyl acetate (ISO) at 10(-5) (1microl in 100ml of water). One group was injected with orexin versus saline and the other with leptin versus saline. They were then presented with different concentrations (lower than 10(-5)) of ISO-odorized water to compare their ability to avoid the ISO-drink. Orexin decreased ISO-drink consumption, showing increased avoidance of the ISO concentrations tested which ranged from 10(-9) to 10(-7). Conversely, the administration of leptin resulted in a dose dependant increase in the odorized-drink consumption for ISO 10(-10). Orexin therefore increases and leptin decreases olfactory sensitivity. Orexin and leptin modulate the olfactory performance in a similar way as do physiological induced fasting and satiation and appear to be important factors in the interdependency of olfaction and food intake.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.bbr.2007.05.033 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Investigating the Preventive Effects of Oral Consumption of Dactylorhiza Maculate (Salep) Hydro-alcoholic Extract on Appetite and Body Weight in Male Rats.
Arch Razi Inst
April 2024
Student Research Committee, Jahrom University of Medical Sciences, Jahrom, Iran.
Obesity is the result of positive energy balance in which various hormones and neurotransmitters are involved. Using Dietary supplements is a common and popular method to lose weight. Medicinal plants with specific effects on metabolizing enzymes, blocking adipogenesis, and improving energy metabolism can be a suitable alternative to these supplements.
View Article and Find Full Text PDFMetabolic Pathophysiology of Cortical Spreading Depression: A Review.
Brain Sci
October 2024
Department of Biomedical Science, Noorda College of Osteopathic Medicine, Provo, UT 84606, USA.
Cortical spreading depression (CSD) is an electrophysiologic pathological state in which a wave of depolarization in the cerebral cortex is followed by the suppression of spontaneous neuronal activity. This transient spread of neuronal depolarization on the surface of the cortex is the hallmark of CSD. Numerous investigations have demonstrated that transmembrane ion transport, astrocytic ion clearing and fatigue, glucose metabolism, the presence of certain genetic markers, point mutations, and the expression of the enzyme responsible for the production of various arachidonic acid derivatives that participate in the inflammatory response, namely, cyclooxygenase (COX), all influence CSD.
View Article and Find Full Text PDFA subcortical feeding circuit linking an interoceptive node to jaw movement.
Nature
December 2024
Laboratory of Molecular Genetics, Howard Hughes Medical Institute, The Rockefeller University, New York, NY, USA.
The brain processes an array of stimuli, enabling the selection of appropriate behavioural responses, but the neural pathways linking interoceptive inputs to outputs for feeding are poorly understood. Here we delineate a subcortical circuit in which brain-derived neurotrophic factor (BDNF)-expressing neurons in the ventromedial hypothalamus (VMH) directly connect interoceptive inputs to motor centres, controlling food consumption and jaw movements. VMH neuron inhibition increases food intake by gating motor sequences of feeding through projections to premotor areas of the jaw.
View Article and Find Full Text PDFGrowth Hormone Receptor in Lateral Hypothalamic Neurons Is Required for Increased Food-Seeking Behavior during Food Restriction in Male Mice.
J Neurosci
November 2024
Department of Physiology and Biophysics, Instituto de Ciencias Biomedicas, Universidade de Sao Paulo, Sao Paulo 05508-000, Sao Paulo, Brazil
Growth hormone (GH) action in the brain regulates neuroendocrine axes, energy and glucose homeostasis, and several neurological functions. The lateral hypothalamic area (LHA) contains numerous neurons that respond to a systemic GH injection by expressing the phosphorylated STAT5, a GH receptor (GHR) signaling marker. However, the potential role of GHR signaling in the LHA is unknown.
View Article and Find Full Text PDFNeuropeptide Network of Polycystic Ovary Syndrome - A Review.
Protein Pept Lett
December 2024
Department of Physiology, Dr. ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai 600 113, India.
Article Synopsis
- * Recent research points to a neuroendocrine origin for PCOS, suggesting that hormonal and brain circuit interactions may play a key role in the disorder's symptoms, such as polycystic ovaries and insulin resistance.
- * The review highlights various neuropeptides (like Kisspeptin and Ghrelin) and their potential roles in PCOS, aiming to establish new drug targets that could improve treatment options for the condition.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!