ET-A ( Ki = 4.7 nM ); ET-B ( Ki = 95 nM )

体外活性：波生坦竞争性拮抗[125 I]标记的ET-1对人平滑肌细胞（ET-A受体）、人胎盘（ET-B受体）的特异性结合。波生坦还抑制猪气管上选择性 ET-B 配体的结合。离体大鼠主动脉 (ET-A) 中 ET-1 诱导的收缩和大鼠气管中选择性 ET-B 激动剂 sarafotoxin S6C 诱导的收缩被波生坦竞争性抑制（pA2 分别 = 7.2 和 6.0），内皮依赖性舒张也是如此。兔肠系膜上动脉中sarafotoxin S6C (pA2= 6.7)。波生坦对其他 40 种肽、前列腺素、离子和神经递质的结合没有显着影响，这显示了其对 ET 受体的特异性。细胞测定：进行了一项体外研究，测量波生坦对真皮微血管内皮细胞 (MVEC) 血管生成性能的影响，并检测波生坦抵消系统性硬化症血清抗血管生成作用的能力。研究发现，波生坦显着增加细胞活力，抵消系统性硬化症血清对真皮 MVEC 的抗血管生成作用。

---

波生坦/Bosentan是一种双重内皮素受体拮抗剂，通过逆转Fli1在SSc皮肤成纤维细胞中的转录活性来降低COL1A2基因的表达[2]
之前的报告表明，波生坦是一种双ET受体拮抗剂，可以逆转SSc成纤维细胞的促纤维化表型。然而，Bosentan/波生坦对SSc成纤维细胞发挥显著抗纤维化作用的详细机制仍然未知。我们之前已经证明，Fli1缺乏有助于SSc成纤维细胞中促纤维化表型的建立，而靶向c-Abl/PKC-δ/Fli1通路的甲磺酸伊马替尼逆转了这些细胞的促纤维化表型。鉴于SSc成纤维细胞被转化生长因子β（TGF-β）的自分泌刺激组成型激活，TGF-β是ET-1的强效诱导剂，并产生过量的ET-1，自分泌ET-1似乎参与了SSc成细胞的自激活系统。目前观察到ET-1使Fli1的转录活性失活，这表明波生坦阻断自分泌ET-1通过重新激活Fli1的翻译阻遏物活性逆转了SSc成纤维细胞的促纤维化表型。为了解决这个问题，我们使用培养的SSc皮肤成纤维细胞进行了一系列实验。[2]
支持自分泌ET-1对SSc皮肤成纤维细胞活化的贡献，外源性ET-1不影响I型胶原表达（图5A），而Bosentan/波生坦以剂量依赖的方式抑制I型胶原的表达，对SSc真皮成纤维细胞的细胞存活率没有任何影响（图5B和表1）。此外，在用波生坦治疗的SSc皮肤成纤维细胞中，c-Abl的总水平和磷酸化水平以及PKC-δ的总水平及核定位降低（图5C和5D）。一致地，在用波生坦治疗的SSc皮肤成纤维细胞中，苏氨酸312处的Fli1磷酸化减少（图5E），Fli1在COL1A2启动子上的占有率增加（图5F）。重要的是，波生坦不影响SSc皮肤成纤维细胞中FLI1基因的mRNA水平（图5G）。总的来说，这些结果表明，自分泌ET-1有助于激活SSc皮肤成纤维细胞，波生坦通过增加Fli1的DNA结合能力逆转了SSc皮肤成纤维细胞的促纤维化表型。[2]

静脉注射和口服给药后，波生坦均可抑制大 ET-1 的加压反应，作用持续时间长，且无内在激动剂活性。波生坦还抑制 ET-1 和 sarafotoxin S6C 的抑制和升压作用。其药理学特征使波生坦成为治疗与血管收缩相关的临床疾病的潜在有用药物。波生坦是第一个口服非肽混合 ETA/B 受体拮抗剂。波生坦的长期治疗显着提高了慢性心力衰竭大鼠的生存率、血流动力学和心脏重塑。波生坦降低动脉血压的程度与血管紧张素转换酶 (ACE) 抑制剂相似。急性 MI 后患有 CHF 的大鼠服用波生坦可显着降低动脉血压，并且与 ACE 抑制剂具有相加效应。波生坦的急性和慢性治疗还可以通过降低外周和肺血管阻力以及增加 CHF 患者的心输出量来改善全身和肺血流动力学。

---

波生坦增加了BLM诱导的SSc小鼠模型皮损皮肤成纤维细胞中Fli1蛋白的表达[2]
最后，我们研究了波生坦是否会增加BLM诱导的SSc小鼠模型皮损皮肤成纤维细胞中Fli1蛋白的表达，因为之前的报告表明，波生坦可以预防该模型中皮肤纤维化的发展。由于我们可以再现波生坦对BLM治疗小鼠皮肤纤维化的预防作用（图6A），我们在这些小鼠的皮肤样本中对Fli1进行了免疫染色。如图6B所示，在没有波生坦的情况下，BLM处理的小鼠皮肤成纤维细胞中Fli1阳性皮肤成纤维纤维细胞的数量比PBS处理的小鼠减少得多。相比之下，当施用波生坦时，BLM处理的小鼠和PBS处理的小鼠之间Fli1阳性皮肤成纤维细胞的数量相当。重要的是，Fli1和肌成纤维细胞的标志物α-SMA在双重免疫荧光中的信号在大多数皮肤成纤维细胞中是互斥的（图6C），表明Fli1的表达与体内皮肤成纤维纤维细胞的失活密切相关。总的来说，这些结果表明，波生坦通过增加损伤皮肤成纤维细胞中Fli1蛋白的表达，至少部分地预防了BLM诱导的SSc小鼠模型中皮肤纤维化的发展。

---

DSS大鼠最大有效剂量的测定以及观察到马西坦的最大疗效大于Bosentan波生坦[3]
DSS大鼠的MAP升高至约180 mm Hg。不同实验组的MAP和HR基线值相似。急性口服后，macitentan剂量依赖性地降低了DSS大鼠的MAP。最大有效剂量为30mg/kg；该剂量使MAP降低了30±5 mm Hg（表1）。给药后约24小时达到最大效果（Tmax）。急性口服波生坦可剂量依赖性地降低DSS大鼠的MAP。在100 mg/kg的最大有效剂量下，波生坦使MAP降低了15±2 mm Hg（表1），Tmax在6小时。未观察到对HR的影响。根据这些数据，为附加研究选择了30 mg/kg的马西坦和100 mg/kg的波生坦的最大有效剂量。波生坦的Tmax为6小时，马西坦为24小时。

---

使用附加方案在DSS大鼠中确认选择马西坦和Bosentan/波生坦的最大有效剂量[3]
使用附加方案证实了最大有效剂量的马西坦和波生坦的使用：与马西坦上的赋形剂相比，在马西坦30 mg/kg的基础上服用马西坦30mg/kg不会导致额外的MAP降低（-29±2和-28±5 mm Hg）。当波生坦100 mg/kg达到最大效果时，与波生坦上的赋形剂相比，波生坦100mg/kg不会引起额外的MAP降低（分别为-13±2和-14±3 mm Hg；图2）。

---

在DSS大鼠中使用附加方案对马西坦和Bosentan波生坦进行比较[3]
当达到波生坦100 mg/kg的最大效果时，口服马西替坦30 mg/kg，与在波生坦100mg/kg的基础上服用赋形剂相比，MAP额外降低了19 mm Hg（p<0.01）。马西替丹引起的最大降低为33±4 mm Hg（图2）。相反，当达到马西坦30mg/kg的最大效果时，以100mg/kg的剂量口服波生坦，与在马西坦30 mg/kg的基础上服用的赋形剂相比，不会引起额外的MAP降低（图3）。

---

博莱霉素治疗大鼠的最大有效剂量测定，并观察到马西坦的最大疗效大于Bosentan/波生坦[3]
与盐水滴注的大鼠相比，博莱霉素治疗的大鼠MPAP增加了约13 mm Hg。不同实验组的MPAP和HR基线值相似。急性口服macitentan和波生坦可剂量依赖性地降低博莱霉素大鼠的MPAP（表1），而不影响HR（数据未显示）。在30 mg/kg的剂量下，MPAP的最大下降量为12±3 mm Hg，大约在给药后24小时（Tmax）。在300 mg/kg的最大有效剂量下，波生坦使MPAP降低了7±2 mm Hg（表1），Tmax约为6小时。根据这些数据，选择30 mg/kg的马西坦和300 mg/kg的波生坦进行附加研究。波生坦的Tmax为6小时，马西坦为24小时。

---

在博莱霉素治疗的大鼠中使用附加方案确认Bosentan波生坦最大有效剂量的选择[3]
使用附加方案证实了最大有效剂量的马西坦和波生坦的使用：与马西坦上的赋形剂相比，在马西坦30 mg/kg的基础上服用马西坦30mg/kg不会导致额外的MPAP降低（-18±2和-13±2 mm Hg，p=0.112）。同样，如图4所示，与波生坦上的赋形剂相比，当波生坦300 mg/kg达到最大效果时，服用波生坦300mg/kg不会导致额外的MPAP降低（分别为-8±1和-7±1 mm Hg）。

---

在博莱霉素治疗的大鼠中，使用附加方案对马西坦和Bosentan/波生坦进行比较[3]
当波生坦300 mg/kg达到最大效果时，博莱霉素大鼠口服马西坦30 mg/kg，与波生坦300mg/kg上的赋形剂相比，会导致MPAP进一步降低。马西坦在波生坦上引起的最大降低为-11±1 mm Hg（与赋形剂相比，p<0.01）（图4）。相反，当达到马西坦30mg/kg的最大效果时，以300mg/kg的剂量口服波生坦，与在马西坦30 mg/kg的基础上服用的赋形剂相比，没有引起额外的MPAP降低（图5）。

---

无药物相互作用[3]
如图6所示，服用波生坦不会改变马西坦及其活性代谢产物ACT-132577的血浆浓度，排除了波生坦在附加方案中对马西坦药代动力学的影响。

台盼蓝排除试验用于确定细胞的活力。波生坦以推荐浓度（10、20 和 40 μM）应用于人真皮成纤维细胞。 24 小时和 48 小时后评估细胞的活力。使用血细胞计数器测定染色（死）和未染色（活）细胞的数量。

---

细胞活力测定[2]
通过台盼蓝排斥试验评估细胞存活率。用指定浓度的Bosentan/波生坦处理细胞。在24小时和48小时检查细胞活力。用血细胞计数器计数染色（死）和未染色（活）细胞。

---

免疫印迹[2]
将汇合的静止成纤维细胞血清饥饿48小时并收获。在一些实验中，细胞在收获前用ET-1或Bosentan/波生坦刺激指定的时间。如前所述制备全细胞裂解物和核提取物。样品经过十二烷基硫酸钠聚丙烯酰胺凝胶电泳和用指定的一抗进行免疫印迹。使用增强的化学发光技术检测条带。根据一系列试点实验，分别使用核提取物和全细胞裂解物进行免疫印迹时，抗Fli1抗体和抗磷酸Fli1（Thr312）特异性抗体的效果要好得多。

---

实时荧光定量PCR评价COL1A2启动子活性[2]
正常或SSc成纤维细胞在100mm培养皿中生长至50%融合，使用FuGENE6用指定的构建体和pSV-β-半乳糖苷酶（β-GAL）转染。在37°C下孵育过夜后，一些细胞用ET-1或Bosentan/波生坦进一步刺激24小时。收集细胞，使用RT-PCR测定CAT和β-GAL mRNA水平。β-GAL mRNA水平使转染效率正常化。在某些样本中，已证实该方法再现了使用[14C]-氯霉素进行CAT报告分析的规范方法评估的相对启动子活性的结果。引物序列如下：CAT正向5′-TTCCGTCTCAGCACATCCCTGGGTGA-3′和反向5′-CCCATCGGTGAAAACGGGGGCGAA-3′；β-GAL正向5′-TCCACCTTCCCTGGTTA-3′和反向5′-AGAGTCGGGGGGGGGTTTG-3′。

Rats: Rats that are two months old—DSS and Wistar—are employed. Doses ranging from 0.1 to 100 mg/kg (Macitentan) or 3 to 600 mg/kg (Bosentan) are used to measure the pharmacological effects on heart rate (HR), mean arterial pressure (MAP), or mean pulmonary arterial pressure (MPAP), and up to 120 hours after a single gavage. 1) Macitentan is given on top of the maximum effective dose of Bosentan determined by the dose-response curve in order to assess whether Macitentan can offer greater pharmacological activity compared to Bosentan. Secondly, the maximum effective dose of Macitentan is topped off with the same dose of Bosentan. T_max of the first tested compound is the point at which the second compound's maximal effective dose is given.

---

Dose–response curves and add-on protocol [3]
First, dose–response curves of each ERA were constructed in both systemic hypertensive DSS rats and bleomycin-induced pulmonary hypertensive Wistar rats to determine the maximal effective dose and Tmax (time of observed maximal effect) of each ERA. Pharmacological effects on MAP or MPAP and HR were measured up to 120 h after a single gavage at doses ranging from 0.1 to 100 mg/kg (macitentan) or 3 to 600 mg/kg (Bosentan). To determine whether macitentan could provide superior pharmacological activity vs. bosentan, we designed a study in which: 1) macitentan was administered on top of the maximal effective dose of bosentan established by the dose–response curve as shown in Fig. 1, Fig. 2) the same dose of bosentan was administered on top of the maximal effective dose of macitentan. The maximal effective dose of the second compound was administered at Tmax of the first tested compound.

---

Pharmacokinetics [3]
In order to rule out any confounding drug–drug interaction on the pharmacological effect measured, the exposure of macitentan and its active metabolite ACT-132577 was measured in the presence or absence of Bosentan in similar conditions to the add-on protocol. Vehicle or bosentan 300 mg/kg was administered to Wistar rats (n = 6/group) 6 h prior to macitentan 30 mg/kg. Plasma samples were collected at 1, 2, 3, 4, 6, 8 and 24 h after oral administration of macitentan, and quantification of macitentan and ACT-132577 was determined by liquid chromatography coupled to mass spectrometry.

---

Test compounds [3]
Macitentan and Bosentan were supplied by Actelion Pharmaceuticals Ltd. Gelatin 7.5%, administered at 5 mL/kg, was used as vehicle for oral administration of the compounds by gavage.

Absorption, Distribution and Excretion
Absolute bioavailability is approximately 50% and food does not affect absorption.
Bosentan is eliminated by biliary excretion following metabolism in the liver.
18 L
4 L/h [patients with pulmonary arterial hypertension]

---

Metabolism / Metabolites
Bosentan is metabolized in the liver by the cytochrome P450 enzymes CYP2C9 and CYP3A4 (and possibly CYP2C19), producing three metabolites, one of which, Ro 48-5033, is pharmacologically active and may contribute 10 to 20% to the total activity of the parent compound.
Bosentan has known human metabolites that include Hydroxy Bosentan and 4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-hydroxyphenoxy)-[2,2-]bipyrimidinyl-4-yl]-benzenesulfonamide.

---

Biological Half-Life
Terminal elimination half-life is about 5 hours in healthy adult subjects.

Hepatotoxicity
Bosentan is associated with elevations in serum aminotransferase levels above three times the upper limit of the normal range (ULN) in 3% to 18% of patients, averaging 7.6% using currently recommended doses. The enzyme elevations are usually self-limited and are rarely accompanied by symptoms, but can be more marked and persist and require dose reduction or discontinuation (in 3% to 4% of patients). Monthly monitoring of serum aminotransferase levels is recommended, with discontinuation for levels above 8 times the ULN or for values above 5 times the ULN that persist. There have also been rare reports of clinically apparent liver injury with jaundice associated with bosentan use. The onset of illness was usually within 1 to 6 months of starting bosentan, but cases arising during chronic therapy have also been described (Case 1). The enzyme pattern has typically been hepatocellular or mixed. Immunoallergic features are usually not present and autoantibodies are usually absent or present in low titer. Some cases have been severe and fatalities have been reported, but there have been no published reports of chronic hepatitis or vanishing bile duct syndrome attributed to bosentan. Autoimmune and immunoallergic features are usually not present.
Likelihood score: C (probable cause of clinically apparent liver injury).

---

Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
A study in one patient taking bosentan during breastfeeding found very low levels in milk. Another woman breastfed her preterm newborn while taking bosentan and sildenafil with no adverse effects reported. Amounts ingested by the infant are far below doses given to treat infants and would not be expected to cause any adverse effects in breastfed infants.
◉ Effects in Breastfed Infants
A 23-year-old woman with congenital heart disease and pulmonary hypertension was treated during pregnancy with bosentan and sildenafil in unspecified dosages. These drugs and warfarin were continued postpartum. Her infant was delivered at 30 weeks by cesarean section and weighed 1.41 kg at birth. She nursed the infant in the neonatal intensive care unit for 11 weeks "with good outcome" according to the authors, but the infant died at 26 weeks from a respiratory syncytial virus infection.[2]
A woman breastfeeding her 21-month-old infant was taking 20 mg of sildenafil 3 times daily and 125 mg of bosentan twice daily to treat pulmonary arterial hypertension. The drugs were begun more than 6 months postpartum. The mother did not report any possible adverse effects, serious health problem or hospitalization of the infant in the period from birth until day 651 postpartum when the infant continued to be partially breastfed.[1]
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

---

Protein Binding
Greater than 98% to plasma proteins, mainly albumin.

---

Toxicity Summary
Bosentan is well tolerated, and when patients receive appropriate monitoring presents a very low risk for toxicity. However, when given with cyclosporin A, bosentan’s plasma levels increased 30-fold and resulted in severe headaches, nausea, and vomiting. However, no serious adverse effects or toxicity were present in these patients. In one postmarket period, one episode of overdose by a male patient who took 10000 mg of bosentan resulted in nausea, vomiting, hypotension, blurred vision, and sweating. The patient was able to make a full recovery following adequate blood pressure support.

[1]. Pathophysiology . 2003 Sep;9(4):249-256.

[2]. J Pharmacol Exp Ther . 1994 Jul;270(1):228-35.

Bosentan hydrate is a hydrate. It contains a bosentan.
A sulfonamide and pyrimidine derivative that acts as a dual endothelin receptor antagonist used to manage PULMONARY HYPERTENSION and SYSTEMIC SCLEROSIS.
See also: Bosentan (annotation moved to).

---

Bosentan is a sulfonamide, a member of pyrimidines and a primary alcohol. It has a role as an antihypertensive agent and an endothelin receptor antagonist.
Bosentan is a dual endothelin receptor antagonist marketed under the trade name Tracleer by Actelion Pharmaceuticals. Bosentan is used to treat pulmonary hypertension by blocking the action of endothelin molecules that would otherwise promote narrowing of the blood vessels and lead to high blood pressure.
Bosentan anhydrous is an Endothelin Receptor Antagonist. The mechanism of action of bosentan anhydrous is as an Endothelin Receptor Antagonist, and Cytochrome P450 3A Inducer, and Cytochrome P450 2C9 Inducer.
Bosentan is an endothelin receptor antagonist used in the therapy of pulmonary arterial hypertension (PAH). Bosentan has been associated with serum enzyme elevations during therapy and with rare instances of clinically apparent acute liver injury.
Bosentan is a sulfonamide-derived, competitive and specific endothelin receptor antagonist with a slightly higher affinity for the endothelin A receptor than endothelin B receptor. Bosentan blocks the action of endothelin 1, an extremely potent endogenous vasoconstrictor and bronchoconstrictor, by binding to endothelin A and endothelin B receptors in the endothelium and vascular smooth muscle. Bosentan decreases both pulmonary and systemic vascular resistance and is particularly used in the treatment of pulmonary arterial hypertension.
A sulfonamide and pyrimidine derivative that acts as a dual endothelin receptor antagonist used to manage PULMONARY HYPERTENSION and SYSTEMIC SCLEROSIS.

---

Drug Indication
Used in the treatment of pulmonary arterial hypertension (PAH), to improve exercise ability and to decrease the rate of clinical worsening (in patients with WHO Class III or IV symptoms).
FDA Label
Treatment of pulmonary arterial hypertension (PAH) to improve exercise capacity and symptoms in patients with WHO functional class III. Efficacy has been shown in: , , , Primary (idiopathic and familial) PAH; , PAH secondary to scleroderma without significant interstitial pulmonary disease; , PAH associated with congenital systemic-to-pulmonary shunts and Eisenmenger's physiology. , , , Some improvements have also been shown in patients with PAH WHO functional class II. , , Tracleer is also indicated to reduce the number of new digital ulcers in patients with systemic sclerosis and ongoing digital ulcer disease. ,
Treatment of pulmonary arterial hypertension (PAH) to improve exercise capacity and symptoms in patients with World Health Organization (WHO) functional class III. Efficacy has been shown in: primary (idiopathic and familial) PAH; PAH secondary to scleroderma without significant interstitial pulmonary disease; PAH associated with congenital systemic-to-pulmonary shunts and Eisenmenger's physiology. Some improvements have also been shown in patients with PAH WHO functional class II. Stayveer is also indicated to reduce the number of new digital ulcers in patients with systemic sclerosis and ongoing digital-ulcer disease.
Treatment of interstitial pulmonary fibrosis, Treatment of pulmonary arterial hypertension, Treatment of systemic sclerosis

---

Mechanism of Action
Endothelin-1 (ET-1) is a neurohormone, the effects of which are mediated by binding to ET_A and ET_B receptors in the endothelium and vascular smooth muscle. It displays a slightly higher affinity towards ET_A receptors than ET_B receptors. ET-1 concentrations are elevated in plasma and lung tissue of patients with pulmonary arterial hypertension, suggesting a pathogenic role for ET-1 in this disease. Bosentan is a specific and competitive antagonist at endothelin receptor types ET_A and ET_B.

---

Pharmacodynamics
Bosentan belongs to a class of drugs known as endothelin receptor antagonists (ERAs). Patients with PAH have elevated levels of endothelin, a potent blood vessel constrictor, in their plasma and lung tissue. Bosentan blocks the binding of endothelin to its receptors, thereby negating endothelin's deleterious effects.

---

Bosentan (Tracleer) is an orally administered dual endothelin-1 (ET-1) receptor antagonist approved for use in patients with WHO class II (mildly symptomatic) pulmonary arterial hypertension (PAH). Oral bosentan therapy was beneficial and generally well tolerated in patients with mildly symptomatic PAH. In a well designed, placebo-controlled trial in adolescents and adults with mildly symptomatic PAH, pulmonary vascular resistance was significantly reduced with bosentan relative to placebo, but the 6-minute walk distance did not increase significantly. Similarly, pediatric patients (most of whom had mildly symptomatic PAH) in a small uncontrolled trial experienced some improvement in hemodynamic variables with bosentan, but did not experience a significant increase in exercise capacity. Adverse events associated with bosentan were consistent with those seen in other indications, with major concerns being the potential for teratogenicity and hepatotoxicity, for which regular liver function monitoring is recommended. Overall, considering the progressive nature of PAH, bosentan extends the treatment options available to patients with mildly symptomatic PAH. [1]

---

Introduction: Although the pathogenesis of systemic sclerosis (SSc) still remains unknown, recent studies have demonstrated that endothelins are deeply involved in the developmental process of fibrosis and vasculopathy associated with SSc, and a dual endothelin receptor antagonist, bosentan, has a potential to serve as a disease modifying drug for this disorder. Importantly, endothelin-1 (ET-1) exerts a pro-fibrotic effect on normal dermal fibroblasts and bosentan reverses the pro-fibrotic phenotype of SSc dermal fibroblasts. The purpose of this study was to clarify the details of molecular mechanisms underlying the effects of ET-1 and bosentan on dermal fibroblasts, which have not been well studied. Methods: The mRNA levels of target genes and the expression and phosphorylation levels of target proteins were determined by reverse transcription real-time PCR and immunoblotting, respectively. Promoter assays were performed using a sequential deletion of human α2 (I) collagen (COL1A2) promoter. DNA affinity precipitation and chromatin immunoprecipitation were employed to evaluate the DNA binding ability of Fli1. Fli1 protein levels in murine skin were evaluated by immunostaining. Results: In normal fibroblasts, ET-1 activated c-Abl and protein kinase C (PKC)-δ and induced Fli1 phosphorylation at threonine 312, leading to the decreased DNA binding of Fli1, a potent repressor of the COL1A2 gene, and the increase in type I collagen expression. On the other hand, bosentan reduced the expression of c-Abl and PKC-δ, the nuclear localization of PKC-δ, and Fli1 phosphorylation, resulting in the increased DNA binding of Fli1 and the suppression of type I collagen expression in SSc fibroblasts. In bleomycin-treated mice, bosentan prevented dermal fibrosis and increased Fli1 expression in lesional dermal fibroblasts. Conclusions: ET-1 exerts a potent pro-fibrotic effect on normal fibroblasts by activating "c-Abl - PKC-δ - Fli1" pathway. Bosentan reverses the pro-fibrotic phenotype of SSc fibroblasts and prevents the development of dermal fibrosis in bleomycin-treated mice by blocking this signaling pathway. Although the efficacy of bosentan for dermal and pulmonary fibrosis is limited in SSc, the present observation definitely provides us with a useful clue to further explore the potential of the upcoming new dual endothelin receptor antagonists as disease modifying drugs for SSc. [2]

---

Aims: The endothelin (ET) system is a tissular system, as the production of ET isoforms is mostly autocrine or paracrine. Macitentan is a novel dual ETA/ETB receptor antagonist with enhanced tissue distribution and sustained receptor binding properties designed to achieve a more efficacious ET receptor blockade. To determine if these features translate into improved efficacy in vivo, a study was designed in which rats with either systemic or pulmonary hypertension and equipped with telemetry were given macitentan on top of maximally effective doses of another dual ETA/ETB receptor antagonist, bosentan, which does not display sustained receptor occupancy and shows less tissue distribution. Main methods: After establishing dose-response curves of both compounds in conscious, hypertensive Dahl salt-sensitive and pulmonary hypertensive bleomycin-treated rats, macitentan was administered on top of the maximal effective dose of bosentan. Key findings: In hypertensive rats, macitentan 30 mg/kg further decreased mean arterial blood pressure (MAP) by 19 mm Hg when given on top of bosentan 100 mg/kg (n=9, p<0.01 vs. vehicle). Conversely, bosentan given on top of macitentan failed to induce an additional MAP decrease. In pulmonary hypertensive rats, macitentan 30 mg/kg further decreased mean pulmonary artery pressure (MPAP) by 4 mm Hg on top of bosentan (n=8, p<0.01 vs. vehicle), whereas a maximal effective dose of bosentan given on top of macitentan did not cause any additional MPAP decrease. Significance: The add-on effect of macitentan on top of bosentan in two pathological models confirms that this novel compound can achieve a superior blockade of ET receptors and provides evidence for greater maximal efficacy. [3]

C27H31N5O7S

569.63

569.194

157212-55-0

Bosentan; 147536-97-8

185462

White to off-white solid powder

742.3ºC at 760 mmHg

402.8ºC

3.84E-23mmHg at 25°C

5.293

163.26

3

12

11

40

839

0

SXTRWVVIEPWAKM-UHFFFAOYSA-N

InChI=1S/C27H29N5O6S.H2O/c1-27(2,3)18-10-12-19(13-11-18)39(34,35)32-23-22(38-21-9-6-5-8-20(21)36-4)26(37-17-16-33)31-25(30-23)24-28-14-7-15-29-24;/h5-15,33H,16-17H2,1-4H3,(H,30,31,32);1H2

4-tert-butyl-N-[6-(2-hydroxyethoxy)-5-(2-methoxyphenoxy)-2-pyrimidin-2-ylpyrimidin-4-yl]benzenesulfonamide;hydrate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

配方 1 中的溶解度: ≥ 2.5 mg/mL (4.39 mM) (饱和度未知) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将100 μL 25.0 mg/mL澄清DMSO储备液加入到400 μL PEG300中，混匀；然后向上述溶液中加入50 μL Tween-80，混匀；加入450 μL生理盐水定容至1 mL。
*生理盐水的制备：将 0.9 g 氯化钠溶解在 100 mL ddH₂O中，得到澄清溶液。

---

配方 2 中的溶解度: ≥ 2.5 mg/mL (4.39 mM) (饱和度未知) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将 100 μL 25.0 mg/mL澄清DMSO储备液加入900 μL 20% SBE-β-CD生理盐水溶液中，混匀。
*20% SBE-β-CD 生理盐水溶液的制备（4°C，1 周）：将 2 g SBE-β-CD 溶解于 10 mL 生理盐水中，得到澄清溶液。

---

View More

配方 3 中的溶解度: ≥ 2.5 mg/mL (4.39 mM) (饱和度未知) in 10% DMSO + 90% Corn Oil (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将 100 μL 25.0 mg/mL 澄清 DMSO 储备液加入到 900 μL 玉米油中并混合均匀。

---

配方 4 中的溶解度: ≥ 2.5 mg/mL (4.39 mM) (饱和度未知) in 10% EtOH + 40% PEG300 + 5% Tween80 + 45% Saline (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将100 μL 25.0 mg/mL 澄清 EtOH 储备液加入400 μL PEG300 中，混匀；再向上述溶液中加入50 μL Tween-80，混匀；然后加入450 μL 生理盐水定容至1 mL。
*生理盐水的制备：将 0.9 g 氯化钠溶解在 100 mL ddH₂O中，得到澄清溶液。

---

配方 5 中的溶解度: ≥ 2.5 mg/mL (4.39 mM) (饱和度未知) in 10% EtOH + 90% (20% SBE-β-CD in Saline) (这些助溶剂从左到右依次添加，逐一添加), 澄清溶液。
例如，若需制备1 mL的工作液，可将100μL 25.0mg/mL澄清EtOH储备液加入到900μL 20％SBE-β-CD生理盐水中，混匀。
*20% SBE-β-CD 生理盐水溶液的制备（4°C，1 周）：将 2 g SBE-β-CD 溶解于 10 mL 生理盐水中，得到澄清溶液。

---

请根据您的实验动物和给药方式选择适当的溶解配方/方案：
1、请先配制澄清的储备液(如：用DMSO配置50 或 100 mg/mL母液(储备液));
2、取适量母液，按从左到右的顺序依次添加助溶剂，澄清后再加入下一助溶剂。以 下列配方为例说明 (注意此配方只用于说明，并不一定代表此产品 的实际溶解配方):
10% DMSO → 40% PEG300 → 5% Tween-80 → 45% ddH2O (或 saline);
假设最终工作液的体积为 1 mL, 浓度为5 mg/mL: 取 100 μL 50 mg/mL 的澄清 DMSO 储备液加到 400 μL PEG300 中，混合均匀/澄清；向上述体系中加入50 μL Tween-80，混合均匀/澄清；然后继续加入450 μL ddH2O (或 saline)定容至 1 mL；
3、溶剂前显示的百分比是指该溶剂在最终溶液/工作液中的体积所占比例;
4、 如产品在配制过程中出现沉淀/析出，可通过加热(≤50℃)或超声的方式助溶;
5、为保证最佳实验结果，工作液请现配现用！
6、如不确定怎么将母液配置成体内动物实验的工作液，请查看说明书或联系我们;
7、 以上所有助溶剂都可在 Invivochem.cn网站购买。