Measuring oxygen consumption with an all-electronic multi-range digital respirometer
Oxygen consumption of animals is often measured for studies in physiological ecology. Usually a closed respiration chamber containing a carbon-dioxide-absorbing substance is used. Oxygen consumed by the animal is either compensated by reduction of the vessel volume (Kratochvil 1976) or replaced by electrolysis (Heusner etal. 1965; Rufeger 1968, 1980). Manometers of various kinds are always employed for pressure transmission. All chambers are kept at constant temperature by a thermostatically controlled water bath. The advantage of an electrolytic respirometer is that the quantity of oxygen generated is linearly dependent only on current and independent of air pressure and temperature. The breathing air composition before, during, and after measurement is constant. After equilibration such a system allows direct oxygen consumption measurements at various environmental temperatures without making corrections. In the apparatus described here power supply, time pulse generator, constant current generator, and the processor which controls the operation and calculates the results are joined in a common box. In front of it the counter displays and the switch board with optical and acoustic signals are arranged. A newly designed manometer with adjustable sensitivity and an infra-red sensor drives a digital position discriminator. This amplification of the manometer reading permits a very simple zero adjustment. All the usual types of gas chamber may be used, for instance equipment consisting only of an electrolytic cell, respiration chamber, and compensating chamber (Heusner et al. 1965), as well as extensive additional fittings, with pump-driven air circulation and separate carbon dioxide and humidity absorption vessels (Moyat 1957; Rufeger 1968, 1980). Contact manometers constructed earlier may be connected on a separate input.
(APPLICATION OF COULOMETRY TO THE MEASUREMENT OF OXYGEN CONSUMPTION)(FR).
L’appareil decrit permet d’enregistrer pendant de longues durees (jusqu’a deux semaines) de tres faibles consommations d’oxygene (50 μl h−1 a 10.000 μl h−1). On remplace quantitativement le volume d’oxygene consomme par de l’oxygene produit par electrolyse.
Appareil de culture d'organes en milieu liquide continuellement oxygéné
SommaireL'appareil de culture décrit réalisein vitro des conditions d'oxygénation, de nutrition et d'élimination de déchets proches de celles du milieu intérieur. Tout en reposant sur un principle simple, il offre de nouvelles possibilités d'analyse fonctionnelle et quantitative d'organesin vitro.AbstractThe described apparatus offers conditions of oxygenation, nutrition and waste product removalin vitro nearly similar to those in a living organism. Based on a simple principle, it offers new possibilities of functional and quantitative analysis of organsin vitro.ZusammenfassungDas beschriebene Gerät erlaubt es die Versuchsbedingungen der Organkulturin vitro so nahe wie möglich den physiologischen Bedingungen anzupassen: insbesondere die Sauerstoffversorgung, die Nährstoffzufuhr und die Ausscheidung der Stoffwechselendprodukte sind dauernd gewährleistet. Die Einfachheit des Prinzipz ermöglicht mit dem Gerät eine funktionnelle und quantitative Analyse der Aktivität von Organenin vitro.РезюмеОписываемый аппарат для культуры органов создаетin vitro условия снабжения кислородом, питания и выделения продуктов обмена, близкие к тем, которые имеются во внутреннею среде организма.Хотя аппарат и основан на простом принципе, он предоставляет новые возможности количественного исследования функции органовin vitro.