Cardiovascular-compensatory and decompensatory responses in rats anesthetized with pentobarbital compared to chloralose-urethane

The data presented in these studies suggests that rats anesthetized with pentobarbital are better able to compensate for acute blood loss, but are less able to sustain the compensatory effort during hemorrhagic hypotension than rats anesthetized with chloralose-urethane. However, following reinfusion of shed blood the pentobarbital rats are better able to maintain their blood pressure.     

Effect of hypercapnia on the acid base states of the blood in the crab Carcinus maenas (L.) (Crustacea-Decapoda)]

When the crab Carcinus maenas respires in hypercapnic water, a respiratory acidosis occurs, which is progressively compensated by a rise of the blood bicarbonate concentration. The CO2 partial pressure in the blood increases in proportion to the change in ambient CO2 partial pressure. Therefore, the regulation of the acid-base status depends mainly on non-respiratory adjustments of the blood bicarbonate concentrations.     

GlideScope视频喉镜用于经口与经鼻气管插管的临床观察

目的 观察GlideScope视频喉镜经口气管插管和经鼻气管插管的声门暴露情况、插管时间和血流动力学变化. 方法 在全身麻醉下行择期手术的患者200例,ASA Ⅰ～Ⅱ级,分为经口气管插管组和经鼻气管插管组.观察记录两组患者喉部显露分级、气管插管时间、气管插管前后的心率、血压,计算各时间点的收缩压-心率乘积（RPP）. 结果 使用GlideScope视频喉镜喉部显露分级为Ⅰ级和Ⅱ级的比例高达98%;经口插管组和经鼻插管组的插管时间分别为（43.3±9.8）s和（57.9±13.3）S,两组比较有显著差异;经口插管组的患者在气管插管时和气管插管后1～2 min内的心率、血压和RPP较麻醉诱导前显著升高,经鼻插管组的患者在气管插管后1 min时的心率和RPP较麻醉诱导前显著升高. 结论 使用GlideScope视频喉镜可改善喉部显露分级,经口气管插管所需的时间少于经鼻气管插管,而血流动力学变化强于经鼻气管插管.     

The effect of surgery and anesthetic agents on granulocyte-chemiluminescence in whole blood

Summary The effect of anesthesia and major abdominal surgery on zymosan-induced chemiluminescence (CL) of neutrophil granulocytes was evaluated. CL was measured in diluted whole blood taken at distinct intervals within the perioperative period. In addition, blood samples from healthy volunteers were supplemented with ether and halothane to investigate the in vitro effect of these agents. The phagocytosis-induced CL was not found to be depressed by anesthesia and surgery. Only at supranarcotic concentrations was CL reduced. Surgery and anesthesia, therefore, do not appear to impair this defense system significantly under the conditions of this investigation.     

The effect of halothane on the action of alcuronium in the dog.

The effect of halothane on the action of alcuronium on neuromuscular transmission was studied in the intact dog. Electrical and mechanical evoked responses from stimulation of the ulnar nerve were recorded. The administration of 0.5% halothane prolonged the duration of action of alcuronium by about 50%.     

The effect of halothane on the action of alcuronium in the dog

Summary The effect of halothane on the action of alcuronium on neuromuscular transmission was studied in the intact dog. Electrical and mechanical evoked responses from stimulation of the ulnar nerve were recorded. The administration of 0.5% halothane prolonged the duration of action of alcuronium by about 50%.We are indebted to Professor A. Mueller for facilities, help and encouragement. R.S. Jones was the holder of a Royal Society European Exchange Fellowship.     

Observations expérimentales sur l'apnée acapnique chez le Chien

Summary Suppression of the chemo-receptors of the carotid sinus and aorta æreas prolongs the acapnic apnea markedly. Animals deprived of their chemo-receptors may even die in apnea.During hyperventilation, the expiratory position of the thorax increases. During the acapnic apnea the inspiratory position returns progressively to normal. During hyperventilation and acapnic apnea, rhythmic changes occur in the tonus of the respiratory muscles. These changes in tonus occur in normal animals as well as in animals deprived of their chemo-receptors and vagi nerves.In normal dogs, hyperventilation and acapnea do not induce a fall in arterial blood pressure. Arterial hypotension occurs, however, during hyperventilation in dogs deprived of their carotid sinus and aortic innervation. During acapnic apnea, the arterial blood pressure rises in animals deprived of their carotid sinus and aortic nerves. A secondary fall of arterial pressure occurs during prolonged acapnic apnea in these animals.     

Stimulation of cyclo-oxygenase by lidocaine, a pro-lipoperoxidant

Lidocaine, which was recently demonstrated to be a good pro-lipoperoxidant, was tested on in vitro PGs biosynthesis, and on arachidonate-induced arterial hypotension, in the rabbit. In the in vitro experiments, lidocaine alone was a poor stimulant of cyclo-oxygenase, but it enhanced significantly the cyclo-oxygenase activation of uric acid. In the rabbit, lidocaine lowered the i.v. arachidonate dose necessary to obtain a significant drop of blood pressure.     

Stimulation of cyclo-oxygenase by lidocaine,a pro-lipoperoxidant

Summary Lidocaine, which was recently demonstrated to be a good pro-lipoperoxidant, was tested on in vitro PGs biosynthesis, and on arachidonate-induced arterial hypotension, in the rabbit. In the in vitro experiments, lidocaine alone was a poor stimulant of cyclo-oxygenase, but it enhanced significantly the cyclo-oxygenase activation of uric acid. In the rabbit, lidocaine lowered the i.v. arachidonate dose necessary to obtain a significant drop of blood pressure.     

The effect of halothane on in vitro human neutrophil chemotaxis

Summary Increasing concentrations of halothane were shown to sequentially inhibit directed (chemotactic) and random movement of human peripheral blood neutrophils. No influence on neutrophil movement was apparent at clinically important concentrations, halothane may effect neutrophil microtubule and actomyosin microfilament systems.Acknowledgments. We thank Mr Lous Matej for his skillful technical assistance.     

Dopamine-beta-hydroxylase, adrenaline, noradrenaline and dopamine in the venous blood of adrenal gland of man: a comparison with levels in the periphery of the circulation.

In 10 human subjects plasma dopamine-beta-hydroxylase activity was found in the adrenal vein blood to be as high as in the periphery of the circulation. Adrenaline concentration in the adrenal vein blood was in the mean 170 times, noradrenaline concentration 11 times and dopamine concentration little higher than levels in the periphery.     

WNK signalling pathways in blood pressure regulation

Hypertension (high blood pressure) is a major public health problem affecting more than a billion people worldwide with complications, including stroke, heart failure and kidney failure. The regulation of blood pressure is multifactorial reflecting genetic susceptibility, in utero environment and external factors such as obesity and salt intake. In keeping with Arthur Guyton’s hypothesis, the kidney plays a key role in blood pressure control and data from clinical studies; physiology and genetics have shown that hypertension is driven a failure of the kidney to excrete excess salt at normal levels of blood pressure. There is a number of rare Mendelian blood pressure syndromes, which have shed light on the molecular mechanisms involved in dysregulated ion transport in the distal kidney. One in particular is Familial hyperkalemic hypertension (FHHt), an autosomal dominant monogenic form of hypertension characterised by high blood pressure, hyperkalemia, hyperchloremic metabolic acidosis, and hypercalciuria. The clinical signs of FHHt are treated by low doses of thiazide diuretic, and it mirrors Gitelman syndrome which features the inverse phenotype of hypotension, hypokalemic metabolic alkalosis, and hypocalciuria. Gitelman syndrome is caused by loss of function mutations in the thiazide-sensitive Na/Cl cotransporter (NCC); however, FHHt patients do not have mutations in the SCL12A3 locus encoding NCC. Instead, mutations have been identified in genes that have revealed a key signalling pathway that regulates NCC and several other key transporters and ion channels in the kidney that are critical for BP regulation. This is the WNK kinase signalling pathway that is the subject of this review.     

The effect of surgery and anesthetic agents on granulocyte-chemiluminescence in whole blood

The effect of anesthesia and major abdominal surgery on zymosan-induced chemiluminescence (CL) of neutrophil granulocytes was evaluated. CL was measured in diluted whole blood taken at distinct intervals within the perioperative period. In addition, blood samples from healthy volunteers were supplemented with ether and halothane to investigate the in vitro effect of these agents. The phagocytosis-induced CL was not found to be depressed by anesthesia and surgery. Only at supranarcotic concentrations was CL reduced. Surgery and anesthesia, therefore, do not appear to impair this defense system significantly under the conditions of this investigation.     

Action and interaction of two alpha 1-adrenoceptor agonists, methoxamine and St 587, on the rabbit's blood pressure and EEG

In rabbits methoxamine reversed the vasopressor effect of St 587 and abolished the EEG synchronizing action of St 587. The interaction on the blood pressure could be ascribed either to the different chemical structures of St 587 and methoxamine or to partial agonistic properties of St 587. The interaction on the EEG appears to be more complex.     

Action and interaction of two 888-1888-1888-1agonists,methoxamine and St 587, on the rabbit's blood pressure and EEG

Summary In rabbits methoxamine reversed the vasopressor effect of St 587 and abolished the EEG synchronizing action of St 587. The interaction on the blood pressure could be ascribed either to the different chemical structures of St 587 and methoxamine or to partial agonistic properties of St 587. The interaction on the EEG appears to be more complex.     

Chromosomenaberrationen in Tumorasziteszellen des Ehrlich-Karzinoms der Maus nach Röntgenbestrahlungin vivo bei verschiedenen Sauerstoffpartialdrucken

Summary The frequency of radio-induced fragments of chromosomes increases in ascites-cells of the Ehrlich-carcinoma at higher oxygen partial pressure, to which test animals are exposed during irradiation.     

Berechnung von Konzentrationsprofilen in Blutkapillaren und Nierentubuli unter Verwendung derGrätz-Nusseltschen Differentialgleichung

Summary Concentration profiles are computed in blood capillaries and in the artificial perfused proximal tubulus: maximal difference of oxygen partial pressure between wall and centre in lung capillaries 40–60 Torr, in capillaries of the myocard 4–6 Torr. Maximal concentration difference of THO in the proximal tubulus: 8% of the maximum value.     

Technik der Kanülierung des Confluens sinuum beim Kaninchen für Versuche mit partiellem extrakorporellem Kreislauf

Summary Since an adequate venous blood outflow from the internal jugular vein is not available in the rabbit, a method for venous blood outflow from the Confluens sinuum was developed. It appeared to be useful in experiments with partial extracorporal circulation and for partial oxygenation of the blood circulation during haemodialysis.     

L-arginine and pancreatic islet blood flow in anesthetized rats

The aim of the present study was to see if L-arginine, which induces insulin release and is a precursor of the endothelial-derived relaxing factor nitric oxide, affects whole pancreatic and/or islet blood flow. For this purpose, anesthetized male Sprague-Dawley rats were injected intravenously with either saline or L-arginine (25, 100 or 250 mg/kg body weight). All doses of arginine caused a slight increase in blood glucose concentration, while the highest dose (250 mg/kg body weight) also increased insulin concentration. However, no changes in either mean arterial blood pressure, whole pancreatic or islet blood flow could be discerned with any of the doses of arginine used. It is concluded that insulin release is not necessarily associated with an increased islet blood perfusion.     

Plasma adenosine concentrations are elevated in Dahl salt-sensitive rats

We measured plasma levels of adenosine in Dahl salt-sensitive rats (DS) and Dahl salt-resistant rats (DR) to examine the potential role of adenosine in cardiovascular regulation in this type of hypertension. Plasma adenosine concentrations were significantly higher in DS than in DR. The NaCl content in the diet did not affect plasma adenosine concentration in either DS or DR. Significant positive correlation was found between adenosine concentrations and systolic blood pressure when the data for DS and DR were analyzed together. These results suggest that adenosine may play an important role in the pathophysiology of hypertension in DS.