Discovery Biology, Pfizer Global Research and Development, Ramsgate Road, Sandwich CT13 9NJ, United Kingdom.
Neurosci Lett. 2009 Nov 20;465(3):242-7. doi: 10.1016/j.neulet.2009.08.078. Epub 2009 Sep 3.
The ability to achieve and maintain penile erection is necessary for successful copulation. Studies have demonstrated that dopamine receptor stimulation in the paraventricular nucleus (PVN) of the hypothalamus induces penile erection in rodents, and the dopamine agonist apomorphine has been used to treat erectile dysfunction. The aim of this study was to determine the electrophysiological characteristics of PVN neuronal firing activity in anaesthetised rodents during apomorphine-induced erection. Our findings can be placed in two categories; those effects that occur immediately upon apomorphine administration and continue for up to several minutes prior to penile erection, deemed 'pre-erectile', and those effects that were only observed during penile erection and seminal emission. In the pre-erectile period, apomorphine acts on two different populations of PVN neurons to increase or decrease firing rates and increases alpha1 frequency band power in local field potentials. Decreased delta and increased theta frequency power in PVN local field potentials occur only during penile erection and seminal emission. These studies provide further understanding of the coordinated neuronal activity that occurs in the PVN during apomorphine-induced penile erection.
实现和维持阴茎勃起的能力是成功交配所必需的。研究表明，刺激下丘脑室旁核（PVN）中的多巴胺受体可诱导啮齿动物阴茎勃起，多巴胺激动剂阿扑吗啡已被用于治疗勃起功能障碍。本研究旨在确定麻醉啮齿动物在阿扑吗啡诱导勃起过程中 PVN 神经元放电活动的电生理特征。我们的发现可以分为两类；一类是阿扑吗啡给药后立即发生并持续数分钟直至阴茎勃起的“预勃起”效应，另一类是仅在阴茎勃起和精液排放期间观察到的效应。在预勃起期间，阿扑吗啡作用于 PVN 中的两种不同神经元群，增加或降低放电率，并增加局部场电位中的 alpha1 频带功率。PVN 局部场电位中的 delta 降低和 theta 频率功率增加仅发生在阴茎勃起和精液排放期间。这些研究进一步了解了阿扑吗啡诱导阴茎勃起过程中 PVN 中发生的协调神经元活动。
