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Guanethidine treatment does not block the ability of central leptin administration to decrease blood glucose
Jinpin Wang1, Catherine M Wernette, Robert L Judd
1Department of Nutrition and Food Science, Auburn University, Auburn, Alabama 36849, USA.
The Journal of Endocrinology
|July 5, 2008
Summary
Centrally administered leptin helps control high blood glucose in diabetic rats. This study found the sympathetic nervous system is not required for leptin
Area of Science:
- Neuroendocrinology
- Metabolic Research
Background:
- Leptin regulates appetite and metabolism.
- Leptin administration normalizes blood glucose in streptozotocin (STZ)-induced diabetic rats.
- The role of the sympathetic nervous system in leptin's glucose-lowering effects is unclear.
Purpose of the Study:
- To investigate if an intact sympathetic nervous system is necessary for centrally administered leptin to reduce high blood glucose in STZ-induced diabetic rats.
Main Methods:
- Rats were pretreated with guanethidine (sympathetic nervous system blocker) or vehicle.
- Diabetes was induced using streptozotocin (STZ).
- Leptin or vehicle was administered intracerebroventricularly, and blood glucose levels were monitored.
Main Results:
- Guanethidine pretreatment did not prevent leptin from decreasing blood glucose in diabetic rats.
- This indicates the sympathetic nervous system is not the mediator of leptin's glucose-lowering effect.
Conclusions:
- The sympathetic nervous system does not mediate the glucose-lowering effects of centrally administered leptin in STZ-diabetic rats.
- Leptin's mechanism for reducing hyperglycemia in diabetes may involve other pathways.
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