Melatonin induces urethral contraction and increases intraurethral pressure via MT1 receptor activation in female rats
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View abstract on PubMed
Summary
This summary is machine-generated.Melatonin receptors MT1 and MT2 are present in the female urethra. MT1 receptor activation causes urethral smooth muscle contraction, suggesting a new therapeutic target for urinary function.
Area Of Science
- Urology
- Pharmacology
- Neuroendocrinology
Background
- Melatonin, produced by the pineal gland, regulates circadian rhythms via MT1 and MT2 receptors.
- The role of melatonin receptors in the lower urinary tract, specifically the female urethra, is not well understood.
Purpose Of The Study
- To investigate the expression and function of melatonin receptors (MT1 and MT2) in the female urethra.
- To explore the underlying mechanisms of melatonin's action on urethral smooth muscle.
Main Methods
- Quantitative mRNA expression analysis of MT1 and MT2 receptors in human and rat female urethral tissues.
- Pharmacological studies using melatonin receptor agonists and antagonists on isolated rat urethral tissue strips.
- In vivo assessment of urethral perfusion pressure in female rats following agonist administration.
Main Results
- High expression of MT1 and MT2 receptor mRNA was detected in both human and rat female urethras.
- MT1 receptor stimulation led to significant urethral smooth muscle contraction.
- MT1 receptor activation involved Gq protein-dependent intracellular calcium mobilization, causing contraction.
- In vivo administration of melatonin receptor agonists increased urethral perfusion pressure in rats.
Conclusions
- This study provides the first evidence for the expression and functional role of melatonin receptors in the female urethra.
- MT1 receptor activation mediates urethral smooth muscle contraction through intracellular calcium signaling.
- Targeting MT1 receptors may offer a novel pharmacological approach for modulating female urethral function.
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