title: The effect of leptin on feeding-regulating neurons in the rat hypothalamus.
abstract: Intense immunoreactivity for the leptin receptor was detected in the hypothalamic arcuate nucleus (ARC), ventromedial nucleus (VMH), and lateral hypothalamus (LH) by immunohistochemistry. Cytosolic Ca2+ concentration ([Ca2+]i) in single neurons isolated from the ARC, VMH and LH was measured with dual wavelength fura-2 fluorescence imaging. A reduction of the superfusate glucose concentration from 10 to 1 mM increased [Ca2+]i in 21% of ARC neurons and 22% of LH neurons. Leptin at 0.1 nM inhibited the [Ca2+]i increase in 66 and 64% of these glucose-sensitive ARC and LH neurons, respectively. Inversely, 10 mM glucose increased [Ca2+]i in 49% of the VMH neurons, and 0.1 nM leptin at 1 mM glucose also increased [Ca2+]i in 84% of these glucose-responsive neurons. These results reveal that leptin inhibits the ARC and LH neurons and stimulates the VMH neurons via the leptin receptor expressed in these cells.
mesh_terms: D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D005947:Glucose / Q000494:pharmacology; D007026:Hypothalamic Area, Lateral / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D007031:Hypothalamus / Q000166:cytology / Q000187:drug effects* / Q000502:physiology*; D007150:Immunohistochemistry; D020738:Leptin; D008297:Male; D009474:Neurons / Q000187:drug effects* / Q000502:physiology*; D009994:Osmolar Concentration; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014697:Ventromedial Hypothalamic Nucleus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism