Department of Urology, Ludwig-Maximilians University, Munich, Germany.
Urology. 2012 Mar;79(3):745.e5-12. doi: 10.1016/j.urology.2011.10.053. Epub 2011 Dec 23.
To investigate expression and α1-adrenergic regulation of caldesmon in the human prostate. Caldesmon is an important mediator and regulator of contraction in different smooth muscle types. However, this has not been investigated in the prostate to date. The activity of caldesmon may be tightly regulated by serine-789 phosphorylation.
Prostate tissue was obtained from patients undergoing radical prostatectomy. Caldesmon expression was studied by Western blot analysis and immunohistochemistry. The adrenergic regulation of caldesmon phosphorylation was investigated by Western blot analyses with a site- and phosphospecific antibody.
Caldesmon expression was detectable by Western blot analysis in all investigated samples of human prostates (n = 8 patients). Immunoreactivity after staining with a caldesmon antibody was strong in smooth muscle cells, but not observed in glandular or epithelial cells (n = 5 patients). In double fluorescence staining, caldesmon co-localized with α1A-adrenoceptors and α-smooth muscle actin (n = 6 patients). Stimulation of prostate tissue with noradrenaline (30 μM, n = 6 patients) or the α1-adrenergic agonist phenylephrine (10 μM, n = 6 patients) resulted in progressive phosphorylation of caldesmon at serine-789. Noradrenaline-induced caldesmon phosphorylation was 1.5 ± 0.2-fold after 5 minutes (P<.04 vs basal phosphorylation), and 1.6 ± 0.2-fold after 10 minutes (P<.04). Phenylephrine-induced caldesmon phosphorylation was 1.7 ± 0.2-fold after 10 minutes (P<.02 vs basal phosphorylation), and 2.4 ± 0.6-fold after 20 minutes (P<.05).
Caldesmon is an effector of α1-adrenoceptors in the human prostate. Caldesmon activation may be of importance for α1-adrenergic prostate contraction, and during therapy with α1-blockers.
研究钙调蛋白在人前列腺中的表达和 α1-肾上腺素能调节。钙调蛋白是不同平滑肌类型收缩的重要介质和调节剂。然而，迄今为止，前列腺中尚未对此进行研究。钙调蛋白的活性可能受到丝氨酸 789 磷酸化的紧密调节。
从接受根治性前列腺切除术的患者中获得前列腺组织。通过 Western blot 分析和免疫组织化学研究钙调蛋白的表达。通过 Western blot 分析用位点和磷酸特异性抗体研究钙调蛋白磷酸化的肾上腺素能调节。
Western blot 分析可在所有研究的人前列腺样本（n = 8 例患者）中检测到钙调蛋白表达。用钙调蛋白抗体染色后的免疫反应性在平滑肌细胞中很强，但在腺上皮细胞或上皮细胞中未见（n = 5 例患者）。在双重荧光染色中，钙调蛋白与 α1A-肾上腺素能受体和 α-平滑肌肌动蛋白共定位（n = 6 例患者）。用去甲肾上腺素（30 μM，n = 6 例患者）或 α1-肾上腺素能激动剂苯肾上腺素（10 μM，n = 6 例患者）刺激前列腺组织导致钙调蛋白丝氨酸 789 逐渐磷酸化。去甲肾上腺素诱导的钙调蛋白磷酸化在 5 分钟后为基础磷酸化的 1.5 ± 0.2 倍（P<.04），在 10 分钟后为 1.6 ± 0.2 倍（P<.04）。苯肾上腺素诱导的钙调蛋白磷酸化在 10 分钟后为基础磷酸化的 1.7 ± 0.2 倍（P<.02），在 20 分钟后为 2.4 ± 0.6 倍（P<.05）。
钙调蛋白是人前列腺中 α1-肾上腺素能受体的效应物。钙调蛋白的激活可能对 α1-肾上腺素能前列腺收缩很重要，并且在 α1-阻滞剂治疗期间也很重要。
