Galanin-like peptide and the regulation of feeding behavior and energy metabolism.
The hypothalamic neuropeptides modulate physiological activity via G protein-coupled receptors (GPCRs). Galanin-like peptide (GALP) is a 60 amino acid neuropeptide that was originally isolated from porcine hypothalamus using a binding assay for galanin receptors, which belong to the GPCR family. GALP is mainly produced in neurons in the hypothalamic arcuate nucleus. GALP-containing neurons form neuronal networks with several other types of peptide-containing neurons and then regulate feeding behavior and energy metabolism. In rats, the central injection of GALP produces a dichotomous action that involves transient hyperphasia followed by hypophasia and a reduction in body weight, whereas, in mice, it has only one action that reduces both food intake and body weight. In the present minireview, we discuss current evidence regarding the function of GALP, particularly in relation to feeding and energy metabolism. We also examine the effects of GALP activity on food intake, body weight and locomotor activity after intranasal infusion, a clinically viable mode of delivery. We conclude that GALP may be of therapeutic value for obesity and life-style-related diseases in the near future.
Department of Anatomy, Showa University School of Medicine, Tokyo, Japan.
Kanako
K
Shiba
Haruaki
H
Kageyama
Fumiko
F
Takenoya
Seiji
S
Shioda
D000595:Amino Acid Sequence; D000818:Animals; D006224:Cricetinae; D004734:Energy Metabolism / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D044089:Galanin-Like Peptide / Q000737:chemistry / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D044088:Receptors, Galanin / Q000737:chemistry / Q000378:metabolism
D044089:Galanin-Like Peptide; D012333:RNA, Messenger; D044088:Receptors, Galanin