Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
2000-12-18
pubmed:abstractText
Obesity in normal animals has been demonstrated to be associated with a decrease in sensitivity to leptin especially as it relates to leptin's capacity to increase sympathetic nerve activity and enhance cardiovascular dynamics. In normal animals leptin has been demonstrated to exert significant regulatory responses by its capacity to increase proopiomelanocortin (POMC) expression and especially the increase in alpha melanocyte stimulating hormone (alphaMSH). These responses to leptin are blocked by a melanocortin-4 (MC-4) receptor antagonist. In this study we investigated the responsiveness of the sympathetic nervous system and cardiovascular system of high fat fed obese animals to the intracerebroventricular (ICV) administration of the POMC products alphaMSH and beta-endorphin (beta-END). We further investigated these responses in obese animals following leptin administration in the presence of MC-4 receptor and opioid receptor blockade. The ICV administration of leptin resulted in an increase in lumbar sympathetic nerve activity (LSNA) and mean arterial pressure (MAP) in normals but decreased it in the obese. The ICV administration of alphaMSH increased the LSNA and MAP in normal animals but to a lesser degree in obese animals. On the other hand beta-endorphin decreased the LSNA and MAP in normal animals but increased it in obese animals. Additionally ICV leptin administration in obese animals in the presence of MC-4 or opioid receptor blockade resulted in an increase in sympathetic activity and a pressor response. From these studies we conclude that obesity in high fat fed animals is characterized by a decreased sensitivity to alphaMSH and a paradoxical response to beta-endorphin and this altered responsiveness may be a factor in the altered leptin resistance characteristic of obese animals.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Agouti Signaling Protein, http://linkedlifedata.com/resource/pubmed/chemical/Dietary Fats, http://linkedlifedata.com/resource/pubmed/chemical/Intercellular Signaling Peptides..., http://linkedlifedata.com/resource/pubmed/chemical/Leptin, http://linkedlifedata.com/resource/pubmed/chemical/Naloxone, http://linkedlifedata.com/resource/pubmed/chemical/Pro-Opiomelanocortin, http://linkedlifedata.com/resource/pubmed/chemical/Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Melanocortin, Type 4, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Corticotropin, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Opioid, http://linkedlifedata.com/resource/pubmed/chemical/alpha-MSH, http://linkedlifedata.com/resource/pubmed/chemical/beta-Endorphin
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0196-9781
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1479-85
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:11068094-Agouti Signaling Protein, pubmed-meshheading:11068094-Animals, pubmed-meshheading:11068094-Blood Pressure, pubmed-meshheading:11068094-Body Weight, pubmed-meshheading:11068094-Dietary Fats, pubmed-meshheading:11068094-Drug Resistance, pubmed-meshheading:11068094-Electrophysiology, pubmed-meshheading:11068094-Female, pubmed-meshheading:11068094-Heart Rate, pubmed-meshheading:11068094-Injections, Intraventricular, pubmed-meshheading:11068094-Intercellular Signaling Peptides and Proteins, pubmed-meshheading:11068094-Leptin, pubmed-meshheading:11068094-Naloxone, pubmed-meshheading:11068094-Obesity, pubmed-meshheading:11068094-Pressoreceptors, pubmed-meshheading:11068094-Pro-Opiomelanocortin, pubmed-meshheading:11068094-Proteins, pubmed-meshheading:11068094-Rats, pubmed-meshheading:11068094-Rats, Wistar, pubmed-meshheading:11068094-Receptor, Melanocortin, Type 4, pubmed-meshheading:11068094-Receptors, Corticotropin, pubmed-meshheading:11068094-Receptors, Opioid, pubmed-meshheading:11068094-Splanchnic Nerves, pubmed-meshheading:11068094-alpha-MSH, pubmed-meshheading:11068094-beta-Endorphin
pubmed:year
2000
pubmed:articleTitle
Leptin resistance in obesity is characterized by decreased sensitivity to proopiomelanocortin products.
pubmed:affiliation
Department of Physiology, Wayne State University School of Medicine, 540 E. Canfield, Detroit, MI 48201, USA.
pubmed:publicationType
Journal Article