一种非同位素5α-还原酶抑制剂体外筛选模型的建立和应用

目的:建立一种非同位素5α-还原酶抑制剂体外筛选模型.方法:从大鼠前列腺组织中提取物5α-还原酶,与底物睾酮(T)以及供氢体NADPH共同组成了一种微量反应体系.反应产物二氢睾酮(DHT)用酶免技术(EIA)测定,以产物生成量确定酶活性;对反应底物、NADPH、酶浓度以及反应最佳温度和时间进行了优化.结果:当底物、NADPH、酶提取物浓度分别为0.25μM、1mM和0.3mg,37℃反应60分钟可获最大酶活性.特异性5α-还原酶抑制剂非那雄胺显著降低5α-还原酶催化产物DHT的生成.进一步对24种中药进行筛选,姜黄、夏枯草等中药提取物具有5α-还原酶抑制剂作用.结论:本文建立的非同位素方法有效、可行,可作为一种体外模型筛选和研究5α-还原酶抑制剂.     

人血浆中非那雄胺的HPLC-MS法测定

目的建立人血浆中非那雄胺的HPLC-MS测定法,以测定志愿者口服非那雄胺片剂后的血药浓度,并对供试制剂和参比制剂的生物等效性进行评价。方法血样经0.1 mol·L^-1NaOH碱化后用重蒸乙酸乙酯提取,进行HPLC-MS分析,色谱柱为Hypersil ODS （5 μm,250 mm×4.6 mm）,流动相为甲醇-水 (85∶15),内标为甲地孕酮,检测离子为m/z 395（非那雄胺）、m/z 407(内标),裂解电压为120 V。20名健康志愿者交叉口服供试片和参比片,计算主要药代动力学参数及相对生物利用度,以判断生物等效性。在1～200 μg·L^-1非那雄胺与内标峰面积比值与浓度线性关系良好（R=0.998 6）, 检测限为0.05　μg·L^-1,回收率为85.9%～98.7%。以AUC_0-24计算的非那雄胺片剂的相对生物利用度为(100±13)%。结论建立的分析方法灵敏、准确、简便。统计学结果表明两种制剂生物等效。     

Effects of in utero exposure to finasteride on androgen-dependent reproductive development in the male rat.

Finasteride is a specific inhibitor of type II 5alpha-reductase, the enzyme that converts testosterone (T) to the more potent androgen receptor agonist dihydrotestosterone (DHT). In utero exposure to androgen receptor antagonists and T biosynthesis inhibitors have induced permanent effects on androgen-sensitive end points such as anogenital distance (AGD), nipple retention, and malformations of the male rat reproductive tract. The objectives of this study were to (1) characterize the dose response of finasteride-mediated alterations in androgen-dependent developmental end points, (2) determine whether prenatal exposure to finasteride permanently decreases AGD or results in nipple retention, and (3) evaluate whether AGD or nipple retention is predictive of adverse alterations in the male reproductive tract. Pregnant Crl:CD(SD)BR rats (n=5-6/group) were gavaged with either vehicle or finasteride at 0.01, 0.1, 1.0, 10, or 100 mg/kg/day on gestation days 12 to 21. All male offspring were monitored individually until necropsy on postnatal day (PND) 90. The present study design has been used previously for other antiandrogens and is sensitive to perturbations of the male rat reproductive tract. Decreases in AGD on PND 1 and increases in areolae-nipple retention on PND 13 were significantly different from controls in all finasteride-exposed male rats. Finasteride-induced changes in AGD and nipple retention were permanent in male rats exposed to finasteride at and above 0.1 mg/kg/day. On PND 90, dorsolateral and ventral prostate lobes were absent in 21 to 24% of rats exposed to 100 mg/kg/day finasteride and weighed significantly less at and above 10 mg/kg/day. In the highest dose group, 73% of animals had ectopic testes, much higher than previously reported. The most sensitive malformation other than decreased AGD and nipple retention was the dose-dependent increase in hypospadias. The lowest observed adverse effect level (LOAEL) for finasteride-induced permanent effects in this study was 0.1 mg/kg/day based on permanent changes in AGD and nipple retention. Finasteride-induced changes in AGD and retention of nipples were highly predictive of hypospadias, ectopic testes, and prostate malformations even though some animals with retained nipples or decreased AGD may not have had other reproductive tract malformations. In summary, prenatal exposure to finasteride specifically inhibited DHT-mediated development with little to no change in T-mediated development.     

Inhibition of neurosteroid synthesis increases asphyxia-induced brain injury in the late gestation fetal sheep

Allopregnanolone (AP) is a potent GABAergic agonist that suppresses CNS activity, seizure threshold, and excitotoxicity in the adult brain. AP is present in the fetal sheep brain and increases rapidly after asphyxial insult due to increased 5alpha-reductase type-2 (5alphaR-2) expression. The aim of this study was to use finasteride to suppress fetal neurosteroid synthesis, and then determine the effect on brain injury, particularly in the hippocampus, of asphyxia induced in utero by brief occlusion of the umbilical cord. Catheters and an inflatable umbilical cord cuff were implanted in fetal sheep at approximately 125 days gestation. Five days later the fetuses received either finasteride (20 mg/kg/h) or vehicle (40% hydroxypropyl-beta-cyclodextrin) for 2 h. The umbilical cord was occluded (UCO) for 5 min at 30 min after starting the infusion. The fetal brain was obtained 24 h later for examination of activated caspase-3 expression as an index of apoptosis, and to measure AP content. Finasteride treatment alone significantly reduced AP content and increased the number of caspase-3 positive cells in the hippocampus, cerebellum, and the subcallosal bundle, indicating that AP modulates the normal rate of apoptosis in the developing brain. UCO in vehicle and finasteride-treated fetuses produced a similar, marked decrease in O2 saturation (5.8+/-0.6%), but after finasteride treatment UCO caused a significantly greater increase in the number of caspase-3 positive cells in the hippocampal cornu ammonis 3 (CA3) (57.3+/-1.6%) compared with the vehicle-treated fetuses. Thus, 5alpha-reduced steroids such as AP may be protective in reducing cell death following acute fetal asphyxia. Perturbation of normal fetal neurosteroid levels in late gestation (e.g. due to preterm birth, or maternal synthetic steroid treatment to induce fetal lung maturation) could adversely affect brain development and increase its vulnerability to injury.     

Imaging prostate cancer (PCa) with [99mTc(CO)3]finasteride dithiocarbamate

This investigation aimed to modify finasteride ( 1 ) to finasteride dithiocarbamate ( 2 ) for subsequent synthesis of the rhenium analogue ( 3 ) and [^99mTc]tricarbonyl complexes ( 4 ), to assess its prostate cancer (PCa) targeting potential in a rat model. To validate the identity of ( 4) , reference ( 3) has been synthesized by using fac‐[Net₄]₂[ReBr₃(CO)₃] precursor and characterized by ¹H‐NMR, ¹³C‐NMR, ESI‐MS, and elemental analysis. The analogue ( 4) was synthesized by using fac‐[^99mTc(H₂O)₃(CO)₃]⁺ precursor, and its structure was confirmed by comparative HPLC by using ( 3) as a reference. Further, the suitability of ( 4) as a PCa imaging agent was investigated in vitro and in vivo. At room temperature, ( 4) had ≥99% radiochemical purity and remained ≥84% stable in serum. In preclinical studies, biodistribution of ( 4) in histopathologically established rat model showed adequately high in vivo uptake in the prostate attracting the possibility of using it for noninvasive imaging of PCa.     

加校正因子的主成分自身对照法同时测定非那雄胺片中2个杂质

目的：建立加校正因子的主成分自身对照法测定非那雄胺片中有关物质的含量。方法：CAPCELL PAK C₁₈色谱柱(4.6′250 mm,5 mm),流动相乙腈-水(45∶55),流速1.0 mL.min_-1,检测波长210 nm,进样量20 mL,柱温30℃。测定非那雄胺与杂质Ⅰ、Ⅱ的标准曲线方程,以斜率计算杂质相对于非那雄胺的校正因子,用相对保留时间确定各杂质的位置。结果：非那雄胺杂质Ⅰ、Ⅱ的相对保留时间分别为0.85与1.30,相对校正因子分别为2.40与0.69。结论：本方法可用于非那雄胺片中有关物质的定性及定量分析,采用加校正因子的主成分自身对照法可以更准确的反映其有关物质的含量。     

纳晶微针联合5%米诺地尔酊治疗男性雄激素脱发的临床观察

目的评估纳晶微针联合5%米诺地尔酊治疗男性雄激素脱发(AGA)的治疗效果及安全性.方法于我院皮肤科门诊收集男性AGA患者90例,随机分为3组,各组均30人.纳晶微针联合外用5%米诺地尔酊(A组)、单独纳晶微针治疗组(B组)和单独外用5%米诺地尔酊治疗组(C组),三组患者均连续治疗24周后评估疗效.结果治疗24周后,医师疗效评分方面:A组明显改善率40%,B组和C组明显改善率均为6.7%,三组患者均有改善.两组间相比,A组与B组(P<0.001)、A组与C组(P<0.001),差异均有统计学意义.患者疗效平均分:A组3.03分>C组1.93分>B组1.73分.两组间对比,A组与B组(P<0.001),A组与C组(P<0.001),差异均具有统计学意义.治疗过程中三组患者均未出现明显不良反应.结论纳晶微针联合5%米诺地尔酊治疗男性AGA比单独应用纳晶微针及单独外用米诺地尔治疗效果更佳,值得临床推广应用.     

术前应用非那雄胺对经尿道前列腺电切术手术效果的影响

目的探讨接受经尿道前列腺电切手术(TURP)前应用非那雄胺对降低良性前列腺增生患者经尿道电切综合征(TURS)效果及其作用机制。方法将接受TURP的良性前列腺增生患者180例随机分成两组,治疗组术前服用非那雄胺,对照组不服用药物。对比两组术中失血情况、术中血钠值,术后免疫组化法检测前列腺组织中血管内皮生长因子(VEGF)表达情况。结果治疗组术中失血量、前列腺组织中VEGF计数低于对照组(P<0.05),术中血钠值高于对照组(P<0.05)。结论术前服用非那雄胺能够防止和减少TURS的发生。