治疗良性前列腺增生的双重选择性α1a/1d受体拮抗剂

良性前列腺增生（BPH）是一种老年男性常见病,研发具有高α1受体亚型选择性的新化合物是目前治疗BPH药物的发展趋势之一。本文综述了用于治疗良性前列腺增生（BPH）的α1a/1d受体拮抗剂的研究进展。     

2,4-二甲氧基苯乙胺类α1-肾上腺素受体拮抗剂的合成、生物活性研究

目的设计合成苯乙胺类α1-肾上腺素受体(α1-AR)拮抗剂,并研究它们对大鼠肛尾肌收缩功能的影响。方法以DDPH为先导化合物设计合成了11个新化合物,以2,6-二甲基苯酚为原料经多步反应得中间体卤代苯氧丙酮,再经还原胺化得目标物。运用大鼠肛尾肌收缩功能实验测定目标物的拮抗活性。结果共合成了11个目的物,其结构经IR、HRMS1、H-NMR确证。结论生物活性测试显示大部分目标化合物均具有一定的α1-AR拮抗活性,化合物Ⅲk拮抗作用和DDPH接近。     

2,4-二甲氧基苯乙胺类α1-肾上腺素受体拮抗剂的合成、生物活性研究

目的设计合成苯乙胺类α1-肾上腺素受体（α1-AR）拮抗剂,并研究它们对大鼠肛尾肌收缩功能的影响。方法以DDPH为先导化合物设计合成了11个新化合物,以2,6-二甲基苯酚为原料经多步反应得中间体卤代苯氧丙酮,再经还原胺化得目标物。运用大鼠肛尾肌收缩功能实验测定目标物的拮抗活性。结果共合成了11个目的物,其结构经IR、HRMS1、H-NMR确证。结论生物活性测试显示大部分目标化合物均具有一定的α1-AR拮抗活性,化合物Ⅲk拮抗作用和DDPH接近。     

1-(2,6-二甲氧基)-2-(3,4-二甲基苯乙氨基)丙烷盐酸盐(DDPH)拮抗α1肾上腺素受体的特性

目的　研究DDPH对α₁-肾上腺素受体(α₁-AR)及其亚型的拮抗作用。方法　放射配体结合实验和离体血管收缩功能实验。结果　DDPH对¹²⁵I-BE2254与大鼠脑皮质和脾脏α₁-AR结合呈竞争性拮抗作用。pK_I值在两者间无显著性差别, Hill系数均接近于1.0。在分别稳定表达α_1A,α_1B或α_1D-AR的克隆HEK293细胞中,其拮抗的pK_I值α_1A和α_1D比α_1B-AR高约2倍,Hill系数均接近于1.0。并拮抗去甲肾上腺素(NE)介导大鼠主动脉,肾动脉和脾脏收缩的pA₂值,在三者间无显著差别,斜率接近1.0。结论　DDPH对α₁-AR有竞争性拮抗作用,但其作用对α₁-AR亚型无选择性。     

新化合物Ⅲ21对大鼠心肌内皮素受体(ETAR,ETBR)亚型的亲和力和选择性

目的研究新化合物Ⅲ21与大鼠心肌内皮素受体(Endothelin receptor,ETR)的亲和力及结合特点.方法采用放射配体受体结合分析方法,通过125I-ET1与大鼠左心室膜受体结合,观察新化合物Ⅲ21对ETR的亲和力及对ETAR,ETBR两种亚型的选择性,分别求IC50值.结果Ⅲ21对125I-ET1与ETR的结合有较强的抑制作用,在10-7mol·L-1浓度时,使其结合率降为原来的(43.1±13.7)%.Ⅲ21抑制125I-ET1与ETAR和ETBR结合的IC50值分别为10.21 nmol·L-1和1.65μmol·L-1,两者比值(ETAR的选择性)为161.76.结论新化合物Ⅲ21与ETR有较强的亲和力,并且对ETAR具有较高的选择性,可能是一种选择性ETA受体拮抗剂.     

一种新的α1A肾上腺素受体选择性拮抗剂—Sertindole

本工作分别在稳定表达α_1A,α_1B和α_1D肾上腺素受体(adrenoceptor,AR)的人胚胎肾脏细胞( human embryonic kidney 293,HEK 293)和大鼠离体血管上,用放射配体结合实验和离体血管收缩功能实验方法以确定sertindole对α₁-AR亚型的选择性拮抗作用。结果显示sertindole与克隆α_1A-AR的亲和性分别是与克隆α_1B-AR和克隆α_1D-AR的69倍和132倍。Sertindole拮抗去甲肾上腺素引起的主动脉和肾动脉收缩反应的pA₂值分别与其对α_1D和α_1A亚型的pKI值相符。分别稳定表达3种亚型受体的HEK293细胞膜标本经与sertindole预温育30min后,受体与¹²⁵IBE2254结合的B_max值显著降低,KD值无显著变化;而在 sertindole 存在条件下,α₁-AR3种亚型与¹²⁵IBE2254 结合的KD值显著增大,但B_max值无显著改变。上述结果表明sertindole为不可逆性竞争性α₁-AR拮抗剂,并有α_1A亚型选择性。     

大鼠前列腺α1-肾上腺素受体亚型分析

用离体组织收缩功能实验和放射配体结合实验, 分析大鼠前列腺α₁-肾上腺素受体(α₁-AR)三种亚型的分布及其介导的收缩效应. 结果显示: 标本经用氯乙基可乐定(CEC)预处理后,去氧肾上腺素(PE)介导的最大收缩效应无明显下降, α₁-AR亚型选择性拮抗剂5-MU, WB4101, 萘哌地尔, 尼古地平, BMY7378抑制PE介导前列腺收缩的pA₂值与克隆α_1A-AR亚型的K_i值呈高度相关(r=0.91). 在放射配体结合实验中, 标本经CEC预处理后, ［¹²⁵I］BE与α₁-AR的最大结合容量由1.09±0.32 nmol·g^-1蛋白质明显下降至0.33±0.08 nmol·g^-1蛋白质. α_1A-, α_1B- , α_1D-AR密度分别约占总受体密度的15%, 65%和20%. 结果提示大鼠前列腺中尽管α₁-AR三种亚型均有分布, 但引起平滑肌收缩的功能性α₁-AR以α_1A-AR为主.     

1,2,5,6-4H-1-烷基-3-取代吡啶类新衍生物对血管内皮细胞功能的调节作用及其构效关系

目的：以槟榔碱为结构母核，设计合成1，2，5，6-4H-1-烷基-3-取代吡啶类新衍生物，分析其对血管内皮细胞功能的影响。方法：采用离体大鼠主动脉环和离体豚鼠回肠收缩实验，分别观察新结构化合物对血管和回肠平滑肌张力的影响；并进一步观察一氧化氮合酶抑制剂L-NAME、环氧酶抑制剂吲哚美辛、M受体亚型非选择性激动剂毛果芸香碱和M受体亚型非选择性拮抗剂阿托品对新结构化合物诱发的血管舒张反应的影响。结果：从100个新化合物中发现4个有舒血管反应，但不激活M受体的化合物，分别是HH91、HH95、HH98、HH103。新化合物HH103诱发的内皮依赖性舒血管反应可被L-NAME所拮抗，但不被吲哚美辛、阿托品和毛果芸香碱拮抗。结论：新化合物可诱发内皮依赖性舒张反应并具有特定构效关系；HH103通过促进内皮细胞释放NO发挥其效应；但其作用特征又与乙酰胆碱不同。     

大鼠左心耳三种亚型α1肾上腺素受体对β肾上腺素受体正性变力效应的不同影响

采用电驱动离体大鼠左心耳收缩功能实验研究三种亚型α₁-肾上腺素受体(AR)激动时对β-AR介导正性变力效应的影响. 结果发现,RS 17053(选择性拮抗α_1A-AR)或WB 4101(选择性拮抗α_1A和α_1D-AR)可使去甲肾上腺素(NE)的累积浓度 收缩效应曲线(CRC)显著左移;在BMY 7378(选择性拮抗α_1D-AR)和RS 17053存在下,NE仅激动α_1B和β-AR,其CRC较单独激动β-AR时显著左移;在WB 4101和去氧肾上腺素(Phe)同时存在下(仅激动α_1B-AR),异丙肾上腺素(Iso)的CRC较对照显著左移;用BMY 7378阻断α_1D-AR后,NE的CRC不发生明显的偏移;用RS 17053和螺哌隆阻断α_1A和α_1B-AR,用Phe仅激动α_1D-AR时,对Iso的CRC也无影响. 结果说明在大鼠左心耳α_1A-AR抑制,α_1B-AR增强,而α_1D-AR则不参与对β-AR介导正性变力效应的调节.     

手性化合物TJ0711对肾上腺素受体拮抗作用的研究

目的测定外消旋TJ0711(R/S-)及其两种旋光异构体(S-和R-)对肾上腺素受体各亚型拮抗作用的强度及相对选择性。方法采用离体器官实验法,以离体豚鼠右心房、气管条、离体大鼠肛尾肌、输精管为标本分别测定受试物对β1和β2,α1和α2肾上腺素受体的拮抗参数(pA2)。结果R/S-、S-及R-TJ0711拮抗β1受体的pA2值分别为:7.35、7.22和7.17;拮抗β2受体的pA2值分别为:6.24、6.11和6.23;拮抗α1受体的pA2值分别为:7.63、7.37和7.33;拮抗α2受体的pA2值分别为:5.70、6.08和5.64。S-和R-TJ0711对4种肾上腺素受体亚型的pA2值差异无显著性。R/S-TJ0711拮抗α1受体的pA2值高于S-和R-TJ0711;对另外3种受体亚型,R/S-TJ0711与拆分体的pA2值差异无显著性。结论在离体器官实验中,S-、R-TJ0711对肾上腺素受体各亚型的拮抗作用无明显差异,二者在拮抗α1受体时表现出协同作用;R/S-、S-和R-TJ0711对β1和α1受体的选择性较高。     

In vitro alpha1-adrenoceptor pharmacology of Ro 70-0004 and RS-100329, novel alpha1A-adrenoceptor selective antagonists.

It has been hypothesized that in patients with benign prostatic hyperplasia, selective antagonism of the alpha1A-adrenoceptor-mediated contraction of lower urinary tract tissues may, via a selective relief of outlet obstruction, lead to an improvement in symptoms. The present study describes the alpha1-adrenoceptor (alpha1-AR) subtype selectivities of two novel alpha1-AR antagonists, Ro 70-0004 (aka RS-100975) and a structurally-related compound RS-100329, and compares them with those of prazosin and tamsulosin. Radioligand binding and second-messenger studies in intact CHO-K1 cells expressing human cloned alpha1A-, alpha1B- and alpha1D-AR showed nanomolar affinity and significant alpha1A-AR subtype selectivity for both Ro 70-0004 (pKi 8.9: 60 and 50 fold selectivity) and RS-100329 (pKi 9.6: 126 and 50 fold selectivity) over the alpha1B- and alpha1D-AR subtypes respectively. In contrast, prazosin and tamsulosin showed little subtype selectivity. Noradrenaline-induced contractions of human lower urinary tract (LUT) tissues or rabbit bladder neck were competitively antagonized by Ro 70-0004 (pA2 8.8 and 8.9), RS-100329 (pA2 9.2 and 9.2), tamsulosin (pA2 10.4 and 9.8) and prazosin (pA2 8.7 and 8.3 respectively). Affinity estimates for tamsulosin and prazosin in antagonizing alpha1-AR-mediated contractions of human renal artery (HRA) and rat aorta (RA) were similar to those observed in LUT tissues, whereas Ro 70-0004 and RS-100329 were approximately 100 fold less potent (pA2 values of 6.8/6.8 and 7.3/7.9 in HRA/RA respectively). The alpha1A-AR subtype selectivity of Ro 70-0004 and RS-100329, demonstrated in both cloned and native systems, should allow for an evaluation of the clinical utility of a 'uroselective' agent for the treatment of symptoms associated with benign prostatic hyperplasia.     

Cell proliferation and Ca(2+)-calmodulin dependent protein kinase activation mediated by alpha 1A- and alpha 1B-adrenergic receptor in HEK293 cells

AIM: To examine the ability of alpha 1-AR subtypes on proliferation and Ca(2+)-calmodulin dependent protein kinase (CCDPK, formerly called MAPK) activation in transfected human embryo kidney 293 (HEK293) cells. METHODS: pREP8/alpha 1A-AR, pREP4/alpha 1B-AR, and pREP9/alpha 1D-AR were transfected, respectively, into HEK293 cells by calcium phosphate precipitation. The expression of alpha 1-AR was detected by radioligand binding assays. DNA synthesis was measured by [3H]thymidine incorporation. CCDPK activity was determined by immunoprecipitation method and myelin basic protein was used as substrate. RESULTS: Three clonal HEK293 cell lines stably expressing alpha 1A- or alpha 1B- or alpha 1D-AR were chosen and characterized by radioligand binding assay with receptor densities of about 0.6 nmol.g-1. Treatment with norepinephrine (NE) in the presence of propranolol for 24 h increased DNA synthesis in HEK293/alpha 1A- or HEK293/alpha 1B-AR cells concentration-dependently, with EC50 values of 48.8 nmol.L-1 (95% confidence limits 9.7-246 nmol.L-1) and 8.4 nmol.L-1 (95% confidence limits 2.1-32.9 nmol.L-1), respectively. The increase of DNA synthesis induced by NE 10 mumol.L-1 was 201% +/- 28% and 269% +/- 44% of basal, and the activation of CCDPK was 171% +/- 84% and 292% +/- 92% of basal in HEK293/alpha 1A-AR and HEK293/alpha 1B-AR cells, respectively. Preincubation with prazosin completely abolished NE-induced CCDPK activation in HEK293/alpha 1A- and alpha 1B-AR cells. Those changes were not found in HEK293/alpha 1D-AR cells. CONCLUSION: The activation of alpha 1A- or alpha 1B-AR but not alpha 1D-AR induces cell proliferation.     

Internalization and distribution of three α1-adrenoceptor subtypes in HEK293A cells before and after agonist stimulation

AIM: To examine the subcellular distribution of the 3 alpha1-adrenoceptor (alpha1-AR) subtypes and their internalization and trafficking upon agonist stimulation in human embryonic kidney 293A cells. METHODS: Confocal real-time imaging, enzyme linked immunosorbent assay (ELISA) and whole cell [3H]-prazosin binding assay were applied to detect the distribution and localization of the 3 alpha1-AR subtypes. RESULTS: alpha1A-AR was found both on the cell surface and in the cytoplasm; alpha1BAR, however, was predominantly detected on the cell surface, while alpha1D-AR was detected mainly in the intracellular compartments. After stimulation with phenylephrine, localization changes were detected by confocal microscopy for alpha1A- and alpha1B-AR,but the localization of alpha1D-AR were unaffected. Phenylephrine stimulation promoted a more rapid internalization of alpha1B-AR than alpha1A-AR. alpha1D-AR internalization was detected only by ELISA. Whole cell [3H]-prazosin binding assay showed that alpha1A-AR functional receptors were detected both on the cell surface and in the cytoplasm; alpha1B-AR, however, were detected predominantly on the cell surface, while alpha1D-AR were detected mainly in intracellular compartments. Phenylephrine stimulation promoted internalization of alpha1A- and alpha1B-AR. CONCLUSION: Phenylephrine stimulation induced changes in the localization of the 3 alpha1-AR.     

Receptor subtype involved in α1-adrenergic receptor-mediated Ca^2＋ signaling in cardiomyocytes

Aim： The enhancement of intracellular Ca^＋signaling in response to α1-adrenergic receptor （α1-AR） stimulation is an essential signal transduction event in the regulation of cardiac functions, such as cardiac growth, cardiac contraction, and cardiac adaptation to various situations. The present study was intended to determine the role（s） of the α1-AR subtype（s） in mediating this response. Methods： We evaluated the effects of subtype-specific agonists and antagonists of the α1- AR on the intracellular Ca^2＋ signaling of neonatal rat ventricular myocytes using a confocal microscope. Results： After being cultured for 48 h, the myocytes exhibited spontaneous local Ca^2＋ release, sparks, and global Ca^2＋ transients. The activation of the α1-AR with phenylephrine, a selective agonist of the α1-AR, dose-dependently increased the frequency of Ca^2＋ transients with an EC5o value of 2.3 larnol/L. Blocking the α1A-AR subtype with 5-methylurapidil （5-Mu） inhi- bited the stimulatory effect of phenylephrine with an IC50 value of 6.7 nmol/L. In contrast, blockade of the α1B-AR and α1D-AR subtypes with chloroethylclonidine and BMY 7378, respectively, did not affect the phenylephrine effect. Similarly, the local Ca^2＋ spark numbers were also increased by the activation of the α1-AR, and this effect could be abolished selectively by 5-Mu. More importantly, A61603, a novel selective α1A-AR agonist, mimicked the effects of phenylephrine, but with more potency （EC50 value =6.9 nmol/L） in the potentiation of Ca^2＋ transients, and blockade of the α1A-AR by 5-Mu caused abolishment of its effects. Conclusion： These results indicate that α1-adrenergic stimulation of intracellular Ca^2＋ activity is mediated selectively by the α1-AR.     

Alfuzosin: an α1-receptor blocker for the treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia

α₁-Receptor blockers have become first-line therapy for the medical management of lower urinary tract symptoms associated with benign prostatic hyperplasia. However, adverse effects such as cardiovascular intolerance can limit their use. This article focuses on alfuzosin, a clinically uroselective, α₁-adrenergic antagonist that is available as a novel once-daily formulation that does not require dose titration. Alfuzosin is less vasoactive than other non-subtype selective α₁-receptor blockers. In addition to effects on lower urinary tract symptoms, it is also used as an adjunct to urethral catheterisation in patients with acute urinary retention related to benign prostatic hyperplasia, and can improve sexual function and health-related quality of life in benign prostatic hyperplasia sufferers.     

Yeast two-hybrid screening for proteins that interact with α1-adrenergic receptors

AIM: To find novel proteins that may bind to alpha1A-adrenergic receptor (alpha1A-AR) and investigate their interactions with the other two alpha1-AR subtypes (alpha1B-AR and alpha1D-AR) with an expectation to provide new leads for the function study of the receptors. METHODS: Yeast two-hybrid assay was performed to screen a human brain cDNA library using the C terminus of alpha1A-AR (alpha1A-AR-CT) as bait. X-Gal assay and o-nitrophenyl-beta-D-galactopyranoside (ONPG) assay were subsequently conducted to further qualitatively or quantitatively confirm the interactions between receptors and the three identified proteins. RESULTS: (1) Selection medium screening identified segments of bone morphogenetic protein-1 (BMP-1), active Bcr-related protein (Abr), and filamin-C as binding partners of alpha1A-AR-CT in yeast cells respectively. Besides, protein segments of BMP-1 and Abr could only specifically interact with alpha1A-AR-CT while filamin-C segment interacted with all three alpha1-AR subtypes. (2) In X-Gal assay, the co-transformants of alpha1A-AR-CT and BMP-1 segments turned strong blue at about 30 min while other positive transformants only developed weak blue at about 5-6 h. (3) In ONPG assay, interaction (shown in beta-galactosidase activity) between alpha1A-AR-CT and BMP-1 segments was about 30 times stronger than that of control (P<0.01), while other positive interactions were only about 2-5 times as strong as those of controls (P<0.05). CONCLUSION: In yeast cells BMP-1, Abr and/or filamin-C could interact with three alpha1-AR subtypes, among which, interaction between BMP-1 and alpha1A-AR was the strongest while other interactions between proteins and receptors were relatively weak.     

Section Review Central & Peripheral Nervous Systems: α1-Adrenoceptor antagonists as treatments for benign prostatic hyperplasia

α₁-Adrenoceptor antagonists, originally targeted towards hypertension, are being increasingly used in the treatment of benign prostatic hyperplasia. The identification of multiple α-adrenoceptor subtypes has resulted in the development of compounds which selectively target prostatic α-adrenoceptors and, therefore, provide the potential to produce greater symptomatic relief than non-selective agents. Current opinion suggests a predominant role for the α₁ A-adrenoceptor subtype in contracting human prostate smooth muscle, although more recent data suggest that a different, but closely related, subtype (α₁L) may be responsible. A number of agents have high affinity for prostatic α-adrenoceptors and selectively reduce prostatic urethral pressure in the absence of overt haemodynamic changes in various animal models. Newer compounds, such as Rec 15/2739 (SB 216,469), SL 89.0591 and SNAP 5089, may offer a potential advantage over existing agents, and prostate-selective α-adrenoceptor antagonists are progressing through to clinical studies.     

Functional α1-adrenergic receptor subtypes in human right gastroepiploic artery

AIM: To study the functional alpha1-adrenergic receptor (alpha1-AR) subtypes in human right gastroepiploic artery (RGA). METHODS: The effects of alpha2-AR, alpha1-AR, and alpha1-AR subtype selective antagonists on norepinephrine (NE)-induced vasoconstriction in isolated human RGA were observed by contractile function experiment. RESULTS: Cumulative concentration-response curves for NE were competitively antagonized in RGA by alpha2-AR selective antagonist yohimbine (pA2 6.82+/-0.28, slope 1.12+/-0.40),alpha1-AR selective antagonist prazosin (pA2 9.77+/-0.22, slope 0.90+/-0.22),alpha1A-AR selective antagonists RS17053 (pA2 8.42+/-0.20, slope 0.93+/-0.20) and 5-MU (pA2 8.42+/-0.22, slope 0.88+/-0.18),alpha1D-AR selective antagonist BMY7378 (pA2 6.84+/-0.32, slope 1.05+/-0.17), and alpha1A-,alpha1B-AR selective antagonist WB4101 (pA2 8.88+/-0.20, slope 1.15+/-0.16). The correlation coefficients between these pA2 values of alpha1-AR selective antagonists with pKi values of which obtained from alpha1A-, alpha1B- and alpha1D-AR cloned cells are 0.95, 0.82, and 0.42. After the vessels were pretreated by chlorethylclonidine (CEC), an alpha1B- and alpha1D-AR irreversible alkylating agent, the pD2 values were changed from 5.9+/-0.5 to 5.6+/-0.6 and the maximal contraction was changed from (8.9+/-3.2) g to (8.0+/-3.2) g, respectively. The difference was not significant. CONCLUSION: In human RGA, the contraction response is mainly mediated by alpha1-AR, of which alpha1A-AR plays an important role, whereas alpha1B- and alpha1D-AR are not involved in the contraction response.     

亲情服务在良性前列腺增生患者围手术期管理中的应用研究

目的:观察良性前列腺增生患者围手术期护理中亲情护理服务的应用价值。方法:选取某院2018年3月~2020年3月所收治的良性前列腺增生患者80例,根据随机数字表法分为实验组和对照组,对照组给予常规护理,实验组给予亲情护理服务,对比两组护理效果和护理满意度。结果:实验组护理效果以及护理满意度均显著优于对照组(P<0.05)。结论:良性前列腺增生患者围手术期护理中实施亲情护理服务,能够有效提高患者护理满意度及舒适度,改善睡眠质量。