Related Experiment Video
Updated: May 22, 2026

Hypothalamic Kisspeptin Neurons as a Target for Whole-Cell Patch-Clamp Recordings
Published on: March 17, 2023
Neuropeptide Y loses its orexigenic effect in rats with lesions of the hypothalamic paraventricular nucleus
1Department of Clinical Medicine, School of Medicine and Life Sciences, Zhejiang University City College, Hangzhou, PR China.
Background:
Both neuropeptide Y (NPY) and ghrelin can enhance the feeding behavior. The purpose of this study was to determine whether NPY and ghrelin are involved in hyperphagia and obesity induced by lesions of the hypothalamic paraventricular nucleus (PVN).
Methods:
Sham-operated control rats and rats subjected to bilateral electrolytic lesions of the PVN were administered NPY (5 μg/rat) by intracerebroventricular infusion or ghrelin (20 μg/kg) by intraperitoneal (i.p.) injection. Control rats were administered the appropriate vehicle by the same route as the drug. We measured the cumulative food intake (FI) for 2 h after infusion of NPY and for 4 h after ghrelin injection.
Results:
NPY significantly increased the cumulative FI in sham-operated rats. In PVN-lesioned rats, however, the cumulative FI at each time point (15 min, 30 min, 1 h, and 2 h) after NPY infusion was not significantly different from vehicle infusion, showing that NPY lost its orexigenic effect in PVN-lesioned rats. Following ghrelin injection, the cumulative FI was greater in PVN-lesioned rats than sham-operated rats, indicating that PVN lesions enhanced the orexigenic effects of ghrelin.
Conclusion:
These results suggest that the hyperphagia and obesity induced by PVN lesions may be related to an increased orexigenic action of ghrelin, but not NPY.
Related Concept Videos
Regulation of Food Intake
Diencephalon: Hypothalamus and Coordination
The hypothalamus interacts with other brain regions, including the pituitary gland, through a direct physical connection called the hypothalamic-pituitary axis. The hypothalamus receives somatic and visceral inputs and...
Neural Regulation
Diencephalon: Anatomical Regions
Chemotherapy-Induced Nausea and Vomiting: Neurokinin-1 Receptor Antagonists

