Thioridazine and EKG anomalies

Summary Acute i.v. infusion but not daily oral administration of thioridazine-HCl in the dog produced EKG anomalies similar to those reported in psychiatric patients taking this drug. Lack of EKG effects after thioridazine-5-sulfoxide infusion and presence of anomalies after thioridazine at equivalent doses suggests further evaluation of the relationship between reported plasma levels of thioridazine and its ring-sulfoxide in association with EKG changes.This study was supported, in part, by a Grant-in-Aid from Boehringer-Ingelheim, Ltd. Sandoz, Inc. kindly provided thioridazine HCl (Mellaril^®) and thioridazine-5-sulfoxide.     

Electrocardiographic changes in anaphylactic shock of the rabbit

Zusammenfassung Die simultane Registrierung des EKG und des Karotisblutdrucks am Kaninchen in der Frühphase des anaphylaktischen Schocks lässt auf eine primäre Herzreaktion schliessen, welche, nicht auf einer Verminderung des Blutdrucks, bzw. des koronaren Perfusionsdrucks, sondern auf einer vorwiegend infolge Koronarkonstriktion eintretenden Abnahme der Herzleistung zu beruhen scheint.     

Über eine spontane Extrasystolie im Schrittmachersystem des Tunicatenherzens (Ciona intestinalis L.)

Summary Some experimental results on action potential (EKG) in the pacemaker system of the tunicata heart (Ciona intestinalis) are presented. Synchronous records of both end and central heart regions show a spontaneous chance of the electrical activity in the middle of the heart tube, just before the periodic reversal of the direction of the pulsating wave starts. Extra systoles in the central pacemaker influence the terminal centres and provoke reversal.

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Herrn Prof.W. v. Buddenbrock zum 80. Geburtstag.     

Preliminary observations concerning the effect of dopamine on uranyl nitrate induced renal failure

Dopamine infusion, when commenced 24 h after the insult, was ineffective in modifying the course of uranyl nitrate induced renal failure in rabbits.     

Potential toxins of acute liver failure and their effects on blood-brain barrier permeability

The effects of potentials toxins of hepatic coma on the blood-brain barrier (BBB) permeability of the rat have been examined using the Oldendorf technique. Classical toxins of hepatic failure such as ammonia, methyl octanoate, mercaptans, and phenol caused significant increases in BBB permeability. A slight increase in permeability occurred following infusion of peroxidized linoleic acid and unconjugated bilirubin but no increase after infusion of bile acids. E. coli endotoxin infused into rats following partial hepatectomy also increased the BBB permeability.     

Autoradiographische Bestimmung der mittleren Verweilzeit neutrophiler Granulozyten im Blut der Ratte mittels Dauerinfusion von3H- Thymidin

Summary Labelling of neutrophil granulocytes in the blood and sputum of rats was followed by autoradiography for 120 h after starting a continuous infusion of³H-thymidine).     

Baroreceptor and sympathetic responses to acebutolol, a beta 1-adrenoceptor-blocking agent, in rabbits.

Baroreceptor activity was increased after i.v. infusion of acebutolol in rabbits with an intact circulation, and in rabbits with a total cardiopulmonary by-pass. In rabbits with an intact circulation, renal nerve activity was reduced.     

The effect of fluorocitrate on urinary calcium and citrate excretion

Summary The renal handling of calcium and citrate was studied in dogs after the administration of fluorocitrate. The drug produced a significant increase in urinary calcium and citrate excretion. Net renal secretion of citrate occurred during the infusion of fluorocitrate since citrate clearances exceeded the glomerular filtration rate.     

Effect of hyperkalemia on insulin secretion

Summary The effect of hyperkalemia on insulin secretion remains undefined. We evaluated portal and peripheral insulin levels in anesthetized dogs after infusions of KCl. The mean maximal increase in peripheral plasma potassium at infusion rates of 0.2 mEq/kg/h was 0.68±0.20 mEq/l. There were no significant increases in either portal or peripheral insulin levels. In contrast, in six dogs whose plasma potassium concentration increased in each case by more than 2.0 mEq/l (infusion rate of 0.5 mEq/kg/h), portal insulin levels increased fivefold (p<0.05). We conclude that only marked increases in plasma potassium concentration stimulate pancreatic insulin secretion.     

Effect of hyperkalemia on insulin secretion

The effect of hyperkalemia on insulin secretion remains undefined. We evaluated portal and peripheral insulin levels in anesthetized dogs after infusions of KCl. The mean maximal increase in peripheral plasma potassium at infusion rates of 0.2 mEq/kg/h was 0.68 +/- 0.20 mEq/l. There were no significant increases in either portal or peripheral insulin levels. In contrast, in six dogs whose plasma potassium concentration increased in each case by more than 2.0 mEq/l (infusion rate of 0.5 mEq/kg/h), portal insulin levels increased fivefold (p less than 0.05). We concluded that only marked increases in plasma potassium concentration stimulate pancreatic insulin secretion.     

Serum cholesterol,anthropometric, electrocardiographic and dietary data in men living under very similar conditions

Zusammenfassung Häftlinge verschiedener Herkunft und Lebensweise, unter gleichen Umständen längere Zeit im Gefängnis, wurden in zwei Gruppen geteilt: 36 Männer mit Serumcholesterolwerten niedriger als 200 mg%, und 101 Männer mit Werten von 200 mg% und mehr. Die Daten von Alter, Länge, Gewicht, Armumfang, Subkutanfett, Brustumfang, EKG, Qualität und Quantität der Ernährung und Energieverbrauch bewiesen, dass Männer mit niedrigen Cholesterolwerten signifikant aktiver, weniger fett und jünger waren als Männer mit höheren Cholesterolwerten.     

Influence of dopamine infusion on plasma prolactin released by kidney capsule transplanted anterior pituitaries

Summary The infusion of dopamine into the renal artery resulted in decreased prolactin release from 3 anterior pituitary glands transplanted under the kidney capsule. Prolactin levels continually decreased over a 5 min period after DA infusion was terminated and thereafter approached preinfusion levels by the end of 10 min.Supported by NSF Research, grant No. 74-17332.The authors wish to express their appreciation to Mrs Cynthia Van De Walle for her outstanding technical assistance in the performance of the prolactin RIA and the statistical analyses. We also appreciate receiving as a gift from the National Institute for Arthritis, Metabolism and Digestive Diseases the rat prolactin used for iodination (RP-I₂) and standards (RP-1).     

Pralidoxime prevents certain teratogenic effects induced by bidrin in quail embryos]

Bidrin treatment of quail embryos results in axial anomalies as well as malformations of the beak and the limbs. Whereas the administration of pralidoxime to teratogen-treated embryos prevents the appearance of the axial anomalies, the morphogenesis of the beak and limbs remains profoundly altered.     

Versuche zur somatischen Beeinflussung der Organbildung pflanzlicher Embryonen

Summary Experiments on influencing cotyledon formation in embryos ofEranthis hiemalis are reported. By treating the seeds with 100–2000 ppm solutions of 2,4-dichlorophenoxyacetic acid, 2,4,5-trichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid, -naphthylacetic acid and even isopropyl N-phenyl carbamate one can obtain significant increases in twinning and in cotyledon anomalies (syncotyly and pleiocotyly of all degrees). Embryos can be successfully treated until approximately 2 weeks after initial opening of the follicles. X-radiations achieve the same effect, with doses of 2000–4000r corresponding to the treatments with 1000–2000 ppm 2,4-D-solutions. By using weaker concentrations and with sudden temperature changes one can likewise raise the percentage of syn-, tri- and tetracotyls, but pleiocotyls of the higher degrees (5 and more cotyledons) appear only when more intensive methods of treatment are employed. These forms which exceed the normal range of variability arise as bud-like embryo regenerates on the as yet undifferentiated original embryo.     

Preliminary observations concerning the effect of dopamine on uranyl nitrate induced renal failure

Summary Dopamine infusion, when commenced 24 h after the insult, was ineffective in modifying the course of uranyl nitrate induced renal failure in rabbits.Acknowledgments. This study was supported in part by the Lillian and Charles Duncan Research Grant for the Investigation of Factors Affecting Atherogenesis. The dopamine was provided by Arnar-Stone Laboratories, Inc.     

Effect of dihydroergocristine infusion on tolbutamide-induced insulin secretion in man.

The insulinemic response to 1 g of tolbutamide i.v. is greatly enhanced (+ 145%) after a 60-min infusion of the alpha-lytic dihydrogenated ergot alkaloid, dihydroergocristine (83.3 micrograms/min, corresponding to a total dose of 5 mg) in 7 healthy subjects. No differences are observed in the glycemic responses.     

Urogastrone-epidermal growth factor is trophic to the intestinal epithelium of parenterally fed rats

The weight of the stomach, small intestine and colon and the mucosal crypt cell production rate of these tissues were significantly decreased after 10 days on an isocaloric TPN diet when compared to orally fed controls. Continuous infusion of recombinant beta urogastrone, at a dose below that needed to inhibit gastric acid secretion, largely prevented this decrease in crypt cell production rate and gastrointestinal tissue weights.     

Urogastrone-epidermal growth factor is trophic to the intestinal epithelium of parenterally fed rats

Summary The weight of the stomach, small intestine and colon and the mucosal crypt cell production rate of these tissues were significantly decreased after 10 days on an isocaloric TPN diet when compared to orally fed controls. Continuous infusion of recombinant beta urogastrone, at a dose below that needed to inhibit gastric acid secretion, largely prevented this decrease in crypt cell production rate and gastrointestinal tissue weights.