Apelin and vasopressin: two work better than one
Catherine Llorens-Cortes1, Francoise Moos
1INSERM, Laboratory of Central Neuropeptides and Regulations of Water Balance and Cardiovascular Functions, CIRB College de France, Paris, France.
Journal of Neuroendocrinology
|June 21, 2012
Summary
Kidney water retention is regulated by vasopressin. However, water excretion is actively controlled by the diuretic neuropeptide apelin, found in hypothalamic neurons.
Area of Science:
- Neuropeptide signaling
- Renal physiology
- Endocrinology
Background:
- Kidney water balance is crucial for homeostasis.
- Vasopressin (antidiuretic hormone) is a key regulator of water retention.
- Water excretion was previously considered a passive process secondary to vasopressin blockade.
Purpose of the Study:
- To investigate the role of apelin in regulating kidney water excretion.
- To challenge the passive model of water excretion.
- To identify the source and neuronal pathways of diuretic neuropeptides.
Main Methods:
- Analysis of neuropeptide production in peripheral tissues and hypothalamic neurons.
- Investigation of hypothalamic neuronal projections to the posterior pituitary.
- Assessment of apelin's diuretic effects.
Main Results:
- Apelin, a diuretic neuropeptide, actively controls water excretion.
- Apelin is produced by hypothalamic neurons, including those co-expressing vasopressin.
- These neurons project to the posterior pituitary, suggesting a direct role in regulating water excretion.
Conclusions:
- Water excretion is an active, neuropeptide-controlled process, not merely passive.
- Apelin represents a novel target for modulating water balance.
- The discovery of apelin's role necessitates a revised understanding of renal water homeostasis.
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