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Updated: Jul 20, 2026
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A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood
Published on: April 28, 2016
Obestatin acts in brain to inhibit thirst
Willis K Samson1, Meghan M White, Christopher Price
1Department of Pharmacological and Physiological Science, Saint Louis University, 1402 South Grand Boulevard, St. Louis, MO 63104, USA. samsonwk@slu.edu
Summary
Obestatin, a peptide hormone, inhibits water drinking in rats, suggesting a role in thirst regulation. Its effects on food intake may be secondary to its impact on water consumption.
Area of Science:
- Neuroendocrinology
- Gastroenterology
- Physiology
Background:
- Obestatin and ghrelin, derived from the same prohormone, have opposing effects on food intake.
- The obestatin receptor GPR39 is found in the brain and pituitary gland.
- Gene expression of obestatin and ghrelin occurs in these key tissues.
Purpose of the Study:
- To investigate the in vivo and in vitro actions of obestatin.
- To determine obestatin's role in regulating water and food intake.
- To explore obestatin's potential effects on growth hormone (GH) secretion.
Main Methods:
- Intracerebroventricular administration of obestatin in rats.
- Inhibition of ANG II-induced water drinking.
- Current-clamp recordings from cultured subfornical organ neurons.
- In vitro studies on pituitary cell cultures assessing GH secretion.
Main Results:
- Obestatin administration inhibited water drinking in various conditions.
- Effects on water intake preceded and were more pronounced than those on food intake.
- Obestatin affected the membrane potential of subfornical organ neurons.
- Obestatin did not alter basal or stimulated GH secretion in pituitary cells.
Conclusions:
- Obestatin may act in the brain to regulate thirst mechanisms.
- Obestatin does not appear to regulate GH secretion via the pituitary gland.
- Inhibition of water drinking by obestatin might be the primary action, with food intake effects being secondary.
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