Water uptake in the intact frog

Pigeon, G; Epstein, Franklin H.

doi:10.1152/ajplegacy.1963.204.2.217

Cited by 8 publications

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“…6), although seasonal differences in passive Na efflux (Ussing & Zerahn, 1951) and in the ion conductance of shunt pathways (Ussing & Windhager, 1964) have been described by others. The influence of season on the effect of saline-exposure on electrical properties (Table 2) is analogous to a seasonal variation in the effect of vasopressin stimulation on Na fluxes (Hererra & Curran, 1963) and water movement (Share & Ussing, 1965), in vitro, and on water uptake by the whole animal (Pigeon & Epstein, 1963). The occurrence of seasonal changes points to the necessity of adequate control experiments in assessing the effects of any agent on skin transport, Acute changes.…”

Section: Discussionmentioning

confidence: 91%

Effect of prolonged saline‐exposure on sodium transport across frog‐skin

Hornby¹,

Thomas²

1969

The Journal of Physiology

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SUMMARY1. Differences in Na transport between skins from Rana temporaria and R. esculenta maintained for up to several weeks in water or 0 7 % saline (0-7 g NaCl in 100 ml. H20), with and without daily injections of 4% saline (4 g NaCl in 100 ml. H20), were measured, in vitro.2. In saline-treated skins, the following changes were found: (a) An increased Na content. (d) A highly significant fall in Na influx, accounting for the reduced I8C; a small reduction in Na efflux was not significant, statistically.(e) The Pitressin-induced increment in I., was usually considerably lower compared with that in water-exposed skins; considered relative to the pre-Pitressin values, however, there were no clear differences.(f) By calculation from the changes in resistance (R) caused by replacement of outer Na2SO4 Ringer by K2S04 Ringer solution, I. Eo, the electromotive force of the active sodium transport system, was moderately, but significantly, reduced, II. R shuntt the shunt path resistance, was moderately, but significantly, increased, and III. Rser' the series path resistance, was considerably, and highly significantly, increased.(g) K influx from outer K2SO4 Ringer solution was reduced. 3. Differences between skins from water-exposed and saline-treated frogs persisted, in vitro, despite the occurrence of anionic-dependent acute changes after mounting in Ringer solution.4. There were seasonal changes in 1,, and in the effects of saline treatment.R. HORNB Y AND S. THOMAS 5. The findings are discussed in terms of decreased permeability of outer barriers to ion-diffusion, and reduced activity of a Na pump.

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Section: Discussionmentioning

confidence: 91%

Effect of prolonged saline‐exposure on sodium transport across frog‐skin

Hornby¹,

Thomas²

1969

The Journal of Physiology

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“…In den Tabellen sind stets die mittleren Fehler der Mittelwerte angegeben. ERGEBNISSE G e w i c h t s~i n d e r u n g e n u n d W a s s e r h a u s h a l t (BRAUN 1951, PIGEON et al 1963, DeYRUV 1964, GI~AIN-OEI~ 1964. Beim Umsetzen der FrSsche von 23 ° nach 70 C wird die Wasseraufnahme erh/Sht.…”

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The influence of light on the temperature adaptation inRana temporaria

Kasbohm

1967

Helgolander Wiss. Meeresunters

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The influence of light on the temperature adaptation in Rana temporaria. Adult Rana temporaria L. males were acclimated to 70 and 230 C under long day, short day and continued darkness, Therea~er their oxygen consumption was measured at 230 C under different light conditions (automatic 24-hour registration). The individuals previously kept in darkness exhibited capacity adaptation in the sense of a compensation; long day acclimated frogs showed a respective adaptation, without change of light conditions, only in regard to the night values. For short day acclimated individuals, the test temperature of 230 C is unnaturally high. This fact may have affected our results and led to curves which are extremely difficult to interpret. The results obtained indicate that it is important to control the light conditions not only during the first acclimation period but also during the experiment proper. The experiments provide hints for the assumption that the known temperature independence of the circadian rhythm is based on a fast, almost ideal compensation. Extirpation of the pineal organ reduces oxygen consumption and causes the capacity adaptation to disappear. Oxygen consumption of muscle homogenates of individuals exposed to light during the daytime showed capacity adaptation in the sense of a compensation. E I N L E I T U N GBei vieten wechselwarmen Tieren iiegen sich Anpassungen des Stoffwechsels an ver~inderte Temperaturen feststellen, die als Leistungsadaptationen bezeichnet werden. Sic haben sowohl fiir einen relativ kurzfristigen Ternperaturwechsel w~ihrend einer bestimrnten Jahreszeit, als auch fiir die jahreszeitlichen Anderungen eine Bedeutung. Bei diesen langfristigen Anpassungen kiSnnen neben der Adaptationstemperatur andere Faktoren wichtig sein, wie z. B. die Tagesl~inge. Daher stellte sich das Ziet dieser Arbeit, die Wirkung beider Faktoren auf den Sauerstoffverbrauch erwachsener intakter Grasfr&che (Rana temporaria L.) und yon Muskelgewebehomogenisaten zu untersuchen.Die Jahreszeit kann den Tieren dutch eine innere Jahresuhr angezeigt werden. Dieser endogene Circaannuus-Rhythmus wird -wie der circadiane -dutch Zeitgeber

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“…Added to the outer surface solution, calcium decreases net sodium transport by changing the size of the intracellular sodium pool. In the intact frog, Pigeon & Epstein (166) found that hypercalcemia resulting from injection of calciferol pro duced a decrease in water uptake, that hyaluronidase had no effect nor did steroids, but that a marked decrease was obtained when a high percentage of carbon dioxide was present in the air. The authors suggest that the carbon dioxide effect may arise from the accompanying pH change which might limit the dissociation of sulfhydryl groups.…”

Section: Concentration Of Urinementioning

confidence: 99%

Kidney, Water, and Electrolytes

Chinard¹

1964

Annu. Rev. Physiol.

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INTRODUCTIONThe evolution of renal physiology has followed an interesting course in the past few years and has reflected the different approaches made possible by the development of new tools and methods of investigation. The improve ment and extension of the micropipetting techniques have brought the study of the control of electrolyte and water excretion from a consideration of balances of input and outgo for the whole kidney to knowledge of the fluxes and their control in segments of individual nephrons. Studies of slices, of homogenates, and of structural components of cells are dovetailing with the micropipetting experiments to provide data relating metabolic activities with electrolyte transport. Morphological studies of the electron microscopists are rapidly being extended to areas involving the renal circulation and its hor monal control. The investigation of the renal handling of a given substance requires consideration not only of renal structure and function but also of the circulation, of metabolic activities, and of the effects on the handling of other substances. The study of fragments of renal tissue is now directly comple mentary to the study of the intact organ in vivo. GLOMERULAR STRUCTURE AND FUNCTIONSome uncertainty remains concerning the initial step in the formation of urine. The applicability of the pore hypothesis to the passage of water and other substances across capillary walls and to the formation of glomerular fluid has been reviewed by Renkin (1). The calculated frequency of the 30-A pores is so small that their detection by electron micrography is considered unlikely. Winne (2) has presented modified derivations for the dilIusion hypothesis and for the pore filtration hypothesis and has proposed criteria for determining which of the processes is operative. In brief, comparison is made of the rate coefficients for transfer by the Fick diffusion equation for concen tration gradients of solute and of the rate coefficients for the thermodynamic and for the Hagen-PoiseuiUe-Pappenheimer equations for transfer of water. Values for the rate coefficients were calculated from older experimental data and the conclusion was reached that the transfers occurred through pores, albeit of a radius or-about 20 A rather than of 30 A. However, the rate coeffi-1 The survey of literature for this review was concluded in June 1963. No attempt has been made to review systematically material published in abstract form nor to provide complete coverage of all full articles.

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Water uptake in the intact frog

Cited by 8 publications

References 0 publications

Effect of prolonged saline‐exposure on sodium transport across frog‐skin

Effect of prolonged saline‐exposure on sodium transport across frog‐skin

The influence of light on the temperature adaptation inRana temporaria

Kidney, Water, and Electrolytes

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