Testosterone deprivation by castration impairs expression of voltage-dependent potassium channels in rat aorta
Autor: | Ping Zhou, Ying Han, Dan Ma, Qianping Gao, Junxian Cao, Lu Fu, Yina Zhang, Fan Qu, Lei Guo, Zhen-Wei Pan |
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Rok vydání: | 2008 |
Předmět: |
Male
medicine.medical_specialty Vascular smooth muscle Patch-Clamp Techniques medicine.drug_class Potassium Blotting Western chemistry.chemical_element Aorta Thoracic Blood Pressure Cell Separation Biology In Vitro Techniques Membrane Potentials chemistry.chemical_compound medicine.artery Internal medicine medicine Potassium Channel Blockers Animals Testosterone Patch clamp 4-Aminopyridine Pharmacology Aorta Androgen Potassium channel Rats Endocrinology Castration chemistry Potassium Channels Voltage-Gated Orchiectomy |
Zdroj: | European journal of pharmacology. 593(1-3) |
ISSN: | 0014-2999 |
Popis: | In this study, we explored the effects of testosterone deprivation on the expression of voltage-dependent potassium (Kv) channels in vascular smooth muscle cells (VSMCs) in rats. Six months after mature male Wistar rats were castrated, functional and posttranscriptional alterations of voltage-dependent potassium channels were detected using isometric tension measurement, whole-cell patch-clamp and western blot analysis. Constriction of aortic artery rings in response to 4-aminopyridine was significantly decreased 6 months after castration. A significant decrease in the amplitude of voltage-dependent potassium currents of aortic artery smooth muscle cells was detected in castrated rats compared with control rats. The level of expression of Kv1.5 channel protein was decreased. The decreased function and suppressed Kv1.5 protein expression of Kv channels after castration were restored by testosterone replacement. We concluded that long-term deprivation of endogenous testosterone in rats significantly attenuated the function of voltage-dependent potassium channels, and that a decreased expression of Kv1.5 channel protein accounted for this alteration. Restoration of physiological concentrations of testosterone restored the impaired function of voltage-dependent potassium channels, which may provide evidence for the beneficial effects of clinical testosterone replacement. |
Databáze: | OpenAIRE |
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