Gender differences in myogenic regulation along the vascular tree of the gerbil cochlea.
Gender differences in myogenic regulation along the vascular tree of the gerbil cochlea.
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DOI：
10.1371/journal.pone.0025659
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发表时间：
2011
期刊：
影响因子：
3.7
通讯作者：
Wangemann P
中科院分区：
文献类型：
--
作者：
Reimann K;Krishnamoorthy G;Wier WG;Wangemann P
由于耳蜗对缺血和氧化应激的敏感性，耳蜗血流的调节对听力至关重要。许多形式的听力损失，如感音神经性听力损失和老年性耳聋，可能涉及或加重血流障碍。动物实验和临床结果进一步表明，听力损失存在性别偏好，男性更容易受到影响。耳蜗血流量的自动调节已经在一些动物模型体内得到证实，这表明与大脑类似，供应耳蜗的血管具有将流量控制在正常范围内的能力，尽管全身血压存在变化。在这里，我们调查了蒙古沙鼠，一个广泛使用的动物模型在听力研究的耳蜗血供的肌源性调节。耳蜗的血液供应起源于基底动脉，然后是小脑前下动脉，在内耳内，由螺旋蜗轴动脉和辐射小动脉供应螺旋韧带和血管纹的毛细血管床。使用同心移液管系统分离和加压雄性和雌性沙鼠的动脉。通过激光扫描显微镜记录响应于管腔压力增加的直径变化。我们的研究结果表明，从男性和女性沙鼠耳蜗血管肌性调节，但有重要的差异。而在雄性沙鼠，螺旋蜗轴动脉和放射状小动脉表现出压力依赖性的张力，在女性，只有放射状小动脉有这种属性。雄性螺旋蜗轴动脉对L-NNA的反应比雌性螺旋蜗轴动脉大，表明NO依赖性机制在雄性沙鼠耳蜗血管的生肌调节中起着比雌性沙鼠更大的作用。
Regulation of cochlear blood flow is critical for hearing due to its exquisite sensitivity to ischemia and oxidative stress. Many forms of hearing loss such as sensorineural hearing loss and presbyacusis may involve or be aggravated by blood flow disorders. Animal experiments and clinical outcomes further suggest that there is a gender preference in hearing loss, with males being more susceptible. Autoregulation of cochlear blood flow has been demonstrated in some animal models in vivo, suggesting that similar to the brain, blood vessels supplying the cochlea have the ability to control flow within normal limits, despite variations in systemic blood pressure. Here, we investigated myogenic regulation in the cochlear blood supply of the Mongolian gerbil, a widely used animal model in hearing research. The cochlear blood supply originates at the basilar artery, followed by the anterior inferior cerebellar artery, and inside the inner ear, by the spiral modiolar artery and the radiating arterioles that supply the capillary beds of the spiral ligament and stria vascularis. Arteries from male and female gerbils were isolated and pressurized using a concentric pipette system. Diameter changes in response to increasing luminal pressures were recorded by laser scanning microscopy. Our results show that cochlear vessels from male and female gerbils exhibit myogenic regulation but with important differences. Whereas in male gerbils, both spiral modiolar arteries and radiating arterioles exhibited pressure-dependent tone, in females, only radiating arterioles had this property. Male spiral modiolar arteries responded more to L-NNA than female spiral modiolar arteries, suggesting that NO-dependent mechanisms play a bigger role in the myogenic regulation of male than female gerbil cochlear vessels.