The assessment of tobacco smoke toxicity in tissue and organ culture: An in vitro arrangement for exposure under defined conditions

Zusammenfassung Eine Apparatur zur Berauchung von Zell-und Organkulturen unter kontrollierten Bedingungen (Anzahl und Dauer der Puffs, Temperatur, Luftfeuchtigkeit) wird beschrieben. Das System basiert auf der Verwendung der Filtrona-Berauchungsmaschine (Cigarette Components Ltd.); die zusätzlichen Elemente können leicht aus laboreigenem Material zusammengestellt werden. Frischrauch und wasserdampfgesättigte Gasmischungen (z.B. Luft/CO₂) können in der Berauchungskammer in variablen Proportionen gemischt werden.     

Studies on eosinophil granulocytes. II. The effect of cytostatics on the uterine response to oestrogen

Zusammenfassung Bei kastrierten, weiblichen Mäusen, die verschiedene Cytostatica zusammen mit einem langwirkenden Oestrogen erhielten, wurde Gewichtszunahme und Eosinophilie des Uterus nach 11 Tagen gemessen. Zwischen den beiden Wirkungen bestanden offensichtlich keine Beziehungen. Das DNA/RNA Verhältnis blieb unverändert.     

A simple technique for testing the in vitro response of rabbit lymphocytes to PHA and allogeneic cells.

Lymphocytes of rabbits can be separated from small quantities of heparinized whole blood using a simple density gradient of Ficoll-Ronpacon 1.09. This separation technique yields a pure suspension of viable cells allowing reproducible results from cultures stimulated either with PHA or allogeneic lymphocytes isolated by the same technique.     

The effect of gonadotropic hormones and the fetal hypophysis on testosterone production by the testis of 18 day mouse fetuses in organ culture]

The production of testosterone (measured by radioimmuno-assay) by the 18-day-old mouse fetal testis may be stimulated specifically by ovine LH (1 ng, p less than 0.005) and HCG in organ culture. A stimulation by FSH is observed only with high doses (10 mug, p less than 0.0005). Prolactin and ACTH have no effect. Age-matched fetal pituitaries increase significantly the testosterone production in the culture medium (p less than 0.0005).     

The influence of the experimental conditions on the renal response to angiotensin in the rat

Résumé Les conditions expérimentales déterminent la réponse rénale à l'angiotensine chez le rat. Antérieurement, on a seulement demontré une réponse natriurétique à cette hormone. Cependant, chez les rats chargés chroniquement de sodium, on a demontré que l'angiotensine en doses de 0,00005–0,005µg/kg/min est toujours anti-natriurétique. Après une opération récente, ou sous anesthésie ou en présence d'une déplétion de sodium, l'angiotensine à ces doses, chez les mêmes animaux, est soit sans effet ou même natriurétique.     

Physiological studies on the effects of nutritional imbalance on the central nervous system. II. Effects of thiamine deficiency on oxidative enzymes in the brain of chicken, Gallus domesticus.

The activitiy levels of succinate dehydrogenase, glutamate dehydrogenase and pyruvate dehydrogenase in the fore, mid and hind brain regions of the thiamine deficient chicken, Gallus domesticus were determined. The activity levels of succinate dehydrogenase and glutamate dehydrogenase in all the 3 regions of brain showed augmentation on inducing thiamine deficiency. In contrast the activity levels of pyruvate dehydrogenase decreased in the brain of thiamine deficient animals. It is suggested that these changes in the oxidative enzymes indicate disturbance caused in the operation of the tricarboxylic acid cycle in thiamine deficiency.     

The effect of thyroid function on the prothrombin time response to warfarin in rats

Zusammenfassung Die Wirkung von Warfarin, einem Anticoagulans der Dicumarolgruppe, ist erhöht bei hyperthyroiden und vermindert bei hypothyroiden Ratten.

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This work was supported by a grant from the National Research Council of Canada.     

Physiological studies on the effects of nutritional imbalance on the central nervous system. II. Effects of thiamine deficiency on oxidative enzymes in the brain of chicken,Gallus domesticus

Summary The activity levels of succinate dehydrogenase, glutamate dehydrogenase and pyruvate dehydrogenase in the fore, mid and hind brain regions of the thiamine deficient chicken,Gallus domesticus were determined. The activity levels of scccinate dehydrogenase and glutamate dehydrogenase in all the 3 regions of brain showed augmentation on inducing thiamine deficiency. In contrast the activity levels of pyruvate dehydrogenase decreased in the brain of thiamine deficient animals. It is suggested that these changes in the oxidative enzymes indicate disturbance caused in the operation of the tricarboxylic acid cycle in thiamine deficiency.     

The effect of alkaloids from Tabernanthe iboga H. Bn. on the response of isolated organs to catecholamines and the possible role of calcium exchange. Case of Ibogaine]

On isolated Rat duodenum, ibogaine (70 mumoles/l) increases the hypertonic effect following the addition of Calcium ions to the organ previously decalcified. Moreover, this alkaloid increases the hypotomic effect resulting from decalcification of the normal organs. These actions are taken into account with the potentiating effects of ibogaine on noradrenaline and dopamine responses observed on rat vas deferens.     

Comparative studies on the covalent binding of the carcinogen benzo(a)pyrene to DNA in various model systems.

The covalent binding of tritiated benzo(a)pyrene (BP) to DNA has been determined in rat liver in vivo, in rat liver perfused in situ, after incubation of BP with liver single cells, with liver homogenate, with liver microsomes and DNA, with fibroblasts from a rat granuloma pouch, and with 2 cell lines. Liver single cells were found to be a valuable compromise between the most sensitive system (microsomal incubation of BP and DNA) and the biologically most relevant system (in vivo).