Differential expression and regulation of leptin receptor isoforms in the rat brain: effects of fasting and oestrogen
| Autor: | Björn Carlsson, Cecilia Karlsson, Pamela A. Bennett, Iain C. A. F. Robinson, Kajsa Lindell, Lena M. S. Carlsson |
|---|---|
| Rok vydání: | 1998 |
| Předmět: |
Gene isoform
Male medicine.medical_specialty Endocrinology Diabetes and Metabolism Receptors Cell Surface In situ hybridization Biology Polymerase Chain Reaction Cellular and Molecular Neuroscience Endocrinology Isomerism Internal medicine Genetic model Gene expression medicine Image Processing Computer-Assisted Animals Cloning Molecular Receptors Cytokine Receptor In Situ Hybridization Brain Chemistry Arc (protein) Leptin receptor Endocrine and Autonomic Systems Leptin digestive oral and skin physiology Brain Estrogens DNA Fasting Rats Rats Zucker Receptors Leptin Female Carrier Proteins DNA Probes hormones hormone substitutes and hormone antagonists |
| Zdroj: | Neuroendocrinology. 67(1) |
| ISSN: | 0028-3835 |
| Popis: | Leptin affects body weight and reproduction mainly via receptors in the central nervous system. Different isoforms of the leptin receptor (leptin-R) exist, including a long isoform (leptin-RL) with signalling capacity and short isoforms (leptin-RS) with unknown function. The aim of this study was to examine leptin-R gene expression in different regions of the brain under conditions with altered body weight, in the female rat, including ovariectomy (OVX), oestradiol (E2) treatment, fasting and a genetic model of obesity (Zucker fa/fa). Leptin-R gene expression was analysed by in situ hybridization using probes recognizing all receptor isoforms (leptin-R) or specifically leptin-RL. Transcripts recognized by the leptin-R probe were abundant in the choroid plexus (CP), arcuate nucleus (ARC), ventromedial nucleus (VMN), thalamus (TH) and piriform cortex (PC). Leptin-RL transcripts were detected in the ARC, VMN, TH and PC but not in the CP. Although no sex difference was observed, leptin-R gene expression was reduced by E2 administration and increased by OVX. Administration of E2 reduced leptin-RL gene expression in the ARC and VMN but did not alter the expression in the TH or PC. OVX had no effect on the expression of leptin-RL mRNA. Fasting also caused a differential regulation of leptin-R mRNAs, with an increase in abundance of leptin-RL transcripts in the TH despite a decrease in leptin-R in this area. Obese Zucker rats had a similar pattern of expression with an increased expression of leptin-RL transcripts in all brain areas analysed and a decrease in leptin-R gene expression. These results demonstrate a differential regulation of leptin-RL and leptin-RS which could provide a mechanism for regulating access to, and sensitivity of, discrete regions of the brain for circulating leptin. We suggest that fasting and E2 alter the balance between leptin-RL and leptin-RS and that this could increase tissue sensitivity to leptin. |
| Databáze: | OpenAIRE |
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