Myocardial injury following endogenous catecholamine release in rabbits

Catecholamines (CAT) given in large doses produce cardiomyopathic changes in several animal species. This study was designed to determine if endogenous release can also induce cardiac injury. Rabbits were infused with doses of tyramine (TYR), ranging from 200 to 500 micrograms/min/kg, i.v. for 90 min. Arterial pressure and heart rate were measured, as were total CAT concentrations, blood gases, pH and glucose. Two days later the animals were killed and cardiac injury assessed using a histological scoring system. All data were compared with controls given saline. Initial CAT averaged 452 pg/ml, rose to 2890 pg/ml after starting TYR, 500 micrograms/min/kg, and remained elevated for the duration of infusion. Circulating CAT levels were a function of TYR dose, and bore a linear relationship to the histological score (P less than 0.001). Development of lesions was unaltered by beta 1 blockade with practolol, but sharply reduced by alpha blockade with phentolamine (P less than 0.01). Pretreatment with insulin also reduced lesion formation, but diabetic (alloxan) rabbits showed no greater CAT injury. It is concluded that endogenous release of CAT induces myocardial injury in the rabbit in a dose-dependent manner. This is unrelated to myocardial O2 demand, and microvascular pathology was absent. Activation of alpha adrenergic pathways is likely the dominant or exclusive mechanism.     

西地那非和酚妥拉明治疗勃起功能障碍的临床疗效比较

目的：比较西地那非和酚妥拉明治疗勃起功能障碍的临床效果和安全性。方法选取2011年6月—2014年6月南京市妇幼保健院收治的勃起功能障碍患者223例,随机分为对照组（n=108例）和治疗组（n=115例）。对照组性交前0.5～1 h口服甲磺酸酚妥拉明片,1片/次;治疗组在性交前0.5～1 h口服枸橼酸西地那非片。首次使用时推荐剂量为50 mg,根据后期个体疗效情况调节剂量,范围在25～100 mg。两组每日最多服用1次,每周至少1次但不超过4次,均连续治疗8周。比较两组的临床疗效,同时比较两组患者治疗前后勃起功能国际指数问卷表（IIEF-5）评分、勃起质量量表（EQS）评分、平均起效时间和性交持续时间。结果治疗后,治疗组和对照组的总有效率分别为86.9%、63.9%,两组总有效率比较差异有统计学意义（P＜0.05）。治疗后,两组IIEF-5评分和EQS评分均较治疗前显著增加,同组治疗前后差异有统计学意义（P＜0.05）,且治疗后,治疗组这两项评分均显著高于对照组,两组比较差异有统计学意义（P＜0.05）。治疗组平均起效时间和平均性交持续时间均显著长于对照组,两组比较差异有统计学意义（P＜0.05）。结论西地那非治疗勃起功能障碍有较好的临床疗效,疗效优于酚妥拉明,可进行临床推广使用。     

三联药物对妊娠期高血压的治疗效果观察

目的探讨硝枼地平、酚妥拉明和硫酸镁三联用药治疗妊娠期高血压的临床疗效及对妊娠结局的影响。方法将我院收治的90例妊娠高血压患者随机分成对照组和观察组。观察组患者给予硫酸镁治疗,对照组给予硝枼地平、酚妥拉明和硫酸镁治疗,比较两组的临床疗效和妊娠结局。结果观察组和对照组的临床总有效率分别为92.31%和74.36%。两组比较,差异有统计学意义（P〈0.05）。与治疗前比较,两组治疗后的平均动脉压均明显降低（P〈0.05）（P〈0.01）,且观察组治疗后平均动脉压明显低于对照组（P〈0.05）,观察组的早产率、胎儿窘迫、新生儿窒息的发生率明显低于对照组（P〈0.05）。结论硝枼地平、酚妥抗明和硫酸镁三联用药治疗妊娠期高血压可明显降低患者血压,临床疗效显著,妊娠结局良好,并发症少,值得临床推广应用。     

乌拉地尔、多巴胺、多巴酚丁胺、速尿合用治疗急性左心衰临床对比观察

目的:观察乌拉地尔与多巴胺、多巴酚丁胺、速尿组成的新强心利尿合剂治疗急性左心衰的临床疗效和安全性。方法:95例急性左心衰患者,分为A、B、C 3组,A组31例,为对照组,予吸氧、镇静、强心、利尿等常规治疗;B组32例,为酚妥拉明组,在常规治疗的基础上,加予酚妥拉明、多巴胺、多巴酚丁胺、速尿合用;C组32例,为乌拉地尔组,在B组的基础上以乌拉地尔代替酚妥拉明。结果:A组显效8例,有效13例,无效10例,总有效率67.7%;B组显效16例,有效10例,无效6例,总有效81.3%;C组显效28例,有效3例,无效1例,总有效率96.9%。A组与B组比P<0.05;A组与C组比P<0.01;B组与C组比P<0.05。结论:乌拉地尔与多巴胺、多巴酚丁胺、速尿合用的新强心利尿合剂治疗急性左心衰,能改善心功能,效果更显著,起效更迅速,使用更安全,可作为急诊科治疗急性左心衰的常规治疗。     

酚妥拉明治疗小儿肺炎的临床效果观察

目的探究酚妥拉明治疗小儿肺炎的临床效果。方法选取100例2013年3月至2014年3月在我院儿科就诊的确诊小儿肺炎的患儿,随机分成对照组和试验组,分别给予常规治疗和常规治疗基础上给予酚妥拉明静脉滴注治疗,比较两组的临床疗效。结果对照组患儿症状消失时间明显长于试验组患儿,住院时间也明显长于试验组患儿,试验组患儿治疗总有效率86%(43例患儿有效),明显高于对照组患儿治疗总有效率60%(30例患儿治疗有效),对照组患儿发热,呕吐,低血压等并发症发生率为18%(9例),明显高于试验组患儿并发症发生率4%(2例),均有P<0.05,差异有统计学意义。结论酚妥拉明治疗小儿肺炎临床疗效良好,可以明显缩短病程和住院时间,提高治疗有效率,同时减少并发症的发生,建议临床上推广使用酚妥拉明治疗小儿肺炎。     

扩血管与缩血管药物联用治疗大咯血临床观察

目的 探讨联用扩血管与缩血管药物治疗大咯血疗效。方法 82例大咯血病人随即分为观察与对照组, 观察组联用扩血管药物与缩血管药物治疗,对照组用其中的一种。结果 观察组显效率为78．0％,总有效率 88．6％;对照组显效率56．1％,总有效率为75．6％,两组比较差异有显著性(P<0．05)。结论 联用扩血管药物与 缩血管药物治疗大咯血疗疗效更好。     

A probable role for norepinephrine in feeding after hypothalamic injection of morphine

When morphine is instilled directly into the ventromedial hypothalamus of rats there is a latent period followed by a prolonged bout of feeding. This enhanced activity may be mediated by the release of norepinephrine; for morphine-induced feeding was depressed by the α-adrenergic receptor blocker phentolamine. Several neurotransmitter agonists and antagonists failed to duplicate this action: propranolol, serotinin, methysergide, apomorphine and haloperidol were ineffective in modifying ingestion elicited after morphine. Unlike apomorphine, dopamine augmented morphine's a feeding effect. This difference may exist because dopamine acts as a precursor for norepinephrine formation in local ventromedial hypothalamic neurons.     

Effect of phentolamine on peripheral venous distensibility in congestive heart failure

Summary Seven patients with congestive heart failure received an infusion of phentolamine, 5 mg per hour for one hour, and seven others, considered as controls, received an infusion of dextrose. The small dose of phentolamine produced a minimal increase in pulse rate, and no significant change in arterial blood pressure and forearm blood flow. Venous distensibility was measured in the forearm by occlusion plethysmography. It was significantly increased by phentolamine, the rise in venous volume being 20–30% greater than in controls for the same effective venous pressure.     

Protein and isoamylase content of rat-submaxillary gland under the influence of α- and β-sympathicolysis

Summary In order to study the function of adrenergic receptors in the submaxillary gland in vivo, rats were treated with the -sympathicolytic, phentolamine (Regitin^®) and with the -sympathicolytic, propranolol (Dociton^®) and the protein, amylase, and isoamylase content of their submaxillary glands were investigated. The protein concentration rises after 3 weeks of - as well as combined -and -sympathicolysis while the amylase concentrations remain, on the whole, unchanged. The pharmacologically induced secretory inhibitions are being discussed in connection with the generally accepted receptor functions.     

Relationship between prostagandin E1, polyphloretin phosphate and alpha and beta adrenoceptor-bound feeding loci in the hypothalamus of sheep

We have previously proposed that prostaglandins (PG) may play a modulating role on hypothalamic areas controlling feeding and energy balance. In the present experiment we have tested in the medial hypothalamus of sheep for interactions between α and β adrenoceptors, PGE₁ and a PG antagonist polyphloretin phosphate (PPP). Sheep were prepared with 6 cannula guides in the hypothalamus. In each sheep following preliminary injection with 1-norepinephrine (1-NE) and dl-isoproterenol (dl-Isop), loci were selected that showed preferentially either α or β adrenoceptor-bound feeding. In the subsequent experiment PGE₁ blocked the 1-NE (α-agonist) elicited feeding in the α-bound feeding loci but PGE₁ elicited feeding when injected into the β-bound feeding loci. The PGE₁-elicited feeding was specifically blocked by a β antagonist (LB-46). The PPP elicited feeding in both α and β-bound feeding loci but the responses were blocked only by the α antagonist (phentolamine) in the α loci and by the β antagonist (LB-46) in the β loci. These responses lend support to our previous conclusions that injection of α agonists into some and β agonists into other hypothalamic sites, but not vice versa will elicit feeding. PGE₁, injected into loci showing differences in sensitivity to adrenoceptor agonists which elicit feeding, results in increased feeding, as in this experiment, or decreased feeding as shown in a previous report. Thus, we conclude that although it is unlikely that systematically produced PG modulate hypothalamic controls on feeding and energy balance because of the dual effect on feeding, there may be an interaction of endogenous hypothalamic PG and adrenoceptors.