Formation of Liquid in the Lungs of the Foetal Lamb

Boston, R.W.; Humphreys, P. W.; Normand, I. C. S.; Reynolds, Eor; Strang, L. B.

doi:10.1159/000240117

Cited by 20 publications

(8 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The composition of tracheal fluid was also similar to previous reports in terms of electrolyte levels and osmolarity (Adamson et al 1969) and protein content (Boston, Humphreys, Normand, Reynolds & Strang, 1968). Sampling of fluid from the fetal digestive tract has also been accomplished previously.…”

Section: Discussionsupporting

confidence: 80%

“…The levels of major electrolytes and osmolarity in amniotic fluid from the sheep used in this study are similar to those reported previously (Mellor & Slater, 1971). The composition of tracheal fluid was also similar to previous reports in terms of electrolyte levels and osmolarity (Adamson et al 1969) and protein content (Boston, Humphreys, Normand, Reynolds & Strang, 1968). Sampling of fluid from the fetal digestive tract has also been accomplished previously.…”

Section: Discussionsupporting

confidence: 80%

See 1 more Smart Citation

Composition and Volume of Fluid Swallowed by Fetal Sheep

et al. 1984

View full text Add to dashboard Cite

SUMMARYOesophageal cannulations were performed in seven fetal sheep between 109 and 128 d of gestation. Fluid swallowed by the fetuses was collected externally and periodically returned to the fetal stomach by a peristaltic pump. The volume of fluid swallowed daily was calculated from the movement of water in a parallel pump circuit. Samples of oesophageal fluid were removed from the collection bag at the same time as tracheal and amniotic fluid samples.

show abstract

Section: Discussionsupporting

confidence: 80%

Section: Discussionsupporting

confidence: 80%

Composition and Volume of Fluid Swallowed by Fetal Sheep

et al. 1984

View full text Add to dashboard Cite

show abstract

“…In this connexion it is interesting that Boston, Humphreys, Reynolds & Strang (1965) found a significantly larger flow of lung lymph in new-born lambs than in adult sheep. Lymph has a higher albumin/globulin ratio than serum in cats and dogs, much the same ratio as plasma in the rabbit and for rat lymph ratios have been reported both higher and lower than those for rat plasma (Yoffey & Courtice, 1956).…”

Section: Discujssionmentioning

confidence: 88%

Acute effects of haemorrhage on the composition of arterial blood in immature and adult rabbits, kittens and cats

Mott¹

1968

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. The fall of haematocrit after stepwise bleeding in rabbits and young kittens was not accompanied by an equivalent fall of plasma nitrogen. The relative failure of plasma nitrogen to decrease after haemorrhage was not attributable to the entry of diffusible nitrogen into the circulation.2. Plasma protein recovery by a combination of stepwise bleeding and viviperfusion was such as to yield values for the whole body/great vessel haematocrit ratio (Fcells) in the normal range in adult cats but significantly below the normal range in young kittens and rabbits. If viviperfusion was not preceded by stepwise bleeding Fcells in the normal range was obtained in young kittens and rabbits.3. The results of electrophoretic examination of pre-and post-haemorrhagic plasma were consistent with the entry of fresh protein into the circulation after haemorrhage occurring preferentially in the albumin fraction, but increase of albumin/globulin ratio was small in adult cats.4. It was concluded that the fall of haematocrit after haemorrhage in young kittens and rabbits was mainly due to the entry of protein rich tissue fluid into the circulation. In adult cats, however, the haematocrit did not always fall and any such fall may have been partly due to a shift of plasma from the periphery to the great vessels.5. The bearing of these observations on the validity of calculation of blood volume from red cell mass and haematocrit during stepwise haemorrhage was considered.

show abstract

“…From lung weight and lymph flow measurements, Humphreys et al (1967) showed that much of the liquid is cleared by lymphatics from the interstitial spaces of the lung over a period of 5-6 hr, but it seems likely that it must be displaced from the alveolar spaces much more rapidly, otherwise efficient gas exchange would not be possible. The experiments with cyanide show that when the secretion is stopped, absorption takes place at 5-18 ml./hr, presumably down the gradient of water activity which exists because of the difference in protein concentration between lung liquid and plasma, exerting an osmotic pressure of about 25 mmHg (see Boston, Humphreys, Normand, Reynolds & Strang (1968) for protein osmotic pressure values). A removal rate of this order fits with the idea that KCN stopped the secretion, but did not affect permeability, because, in the absence of any change in permeability, the rate of absorption would depend on passive permeability to Cl-, the least permeable solute component; which would allow fluid absorption at only the slow rate observed after cyanide.…”

Section: R E Olver and L B Strang Secretion And Absorption Of Lunmentioning

confidence: 99%

Ion fluxes across the pulmonary epithelium and the secretion of lung liquid in the foetal lamb

Olver¹,

Strang²

1974

The Journal of Physiology

312

168

View full text Add to dashboard Cite

2. The permeability sequence of the pulmonary epithelium for alkali metals was, Na+ > K+ > Rb+ > Li+ > Cs+ and that for halides I-Br-> C1-. Permeabilities to alkaline earths were lower than for the other ions, no definite sequence being established.3. There was an electrical potential difference of -1 to -10 mV (mean -4.3 mV) between lung liquid and plasma (lung liquid negative). Plasma/lung liquid chemical activity ratios were less than unity for the halides (Cl-, Br-, I-), and for K+ and Rb+, whereas the ratio of oneway fluxes (plasma --lung liquid)/(lung liquid -+ plasma) was in each case greater than unity. From the difference between the measured flux ratios and those predicted from the forces determining passive flux, it was concluded that the halides, K+ and Rb+ were actively transported from plasma to lung liquid, Cl-being quantitatively the most important. Na+ and Ca2+ appeared to move passively down a gradient of electrochemical potential.R. E. OLVER AND L. B. STRANG 4. When alveolar liquid [HCO ] was artificially raised, a net flux of HCO-from lung liquid against a gradient of electrochemical activity was observed, suggesting active transport of that ion out of lung liquid.5. The addition of KCN to lung liquid stopped the secretion of liquid and absorption took place.

show abstract

Formation of Liquid in the Lungs of the Foetal Lamb

Cited by 20 publications

References 17 publications

Composition and Volume of Fluid Swallowed by Fetal Sheep

Composition and Volume of Fluid Swallowed by Fetal Sheep

Acute effects of haemorrhage on the composition of arterial blood in immature and adult rabbits, kittens and cats

Ion fluxes across the pulmonary epithelium and the secretion of lung liquid in the foetal lamb

Contact Info

Product

Resources

About