Lung morphometry in guinea pigs acclimated to hypoxia during growth

doi:10.1016/0034-5687(80)90112-7

Respiration Physiology

Volume 42, Issue 2, November 1980, Pages 155-169

Respiration Physiolo...

https://doi.org/10.1016/0034-5687(80)90112-7 Get rights and content

Abstract

The effect of chronic hypoxic exposure on lung development has been assessed in growing guinea pigs (Cavia porcellus). Weanling males of initial $W = 229 g$ were acclimated to a P_O₂ of 80 Torr for 2–14 weeks before sacrifice (range of W = 244–965 g). Growth was the same in hypoxic animals as in controls maintained at a P_O₂ of 133 Torr (range of W in controls = 89–1274 g). Lungs were fixed by tracheal installation of glutaraldehyde and examined morphometrically with the electron microscope. Within 3 weeks of exposure, lung volume (vl) and alveolar surface area (S_a) were significantly increased by 32% and 27% respectively in the hypoxia acclimated animals compared to controls of similar W. However, these differences were progressively reduced with increasing time of exposure, and mean values of vl and S_a were not different between groups when W > 900 g. Chronic hypoxia accelerated lung development towards normal adult dimensions to a degree remarkably similar to that reported in cold acclimated guinea pigs. These findings are compatable with the theory of adaptive lung growth mediated by increased pulmonary blood flow, and suggest anatomical limitations to such growth related to an animal's age.

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The answer is probably a negative one. In fact, the gas exchange area of the lungs is not depressed by hypoxia; rather, the opposite has been often observed (Burri and Weibel, 1971; Cunningham et al., 1974; Lechner and Banchero, 1980; Johnson et al., 1985; Sekhon et al., 1995; Sekhon and Thurlbeck, 1996). Furthermore, sustained changes in the level of metabolism during the first postnatal month in rats, either by changes in caloric intake (Sant’Anna and Mortola, 2002) or by cold exposure (Sant’Anna and Mortola, 2003a), had no carry-over effects on the HVR, other than the effects strictly attributable to the alterations in body size.
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^☆: Supported by NIH grant HL-18145 from the National Heart, Lung and Blood Institute.

¹: Supported by fellowships from the National Science Foundation and the National Heart, Lung, and Blood Institute, NIH.

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Lung morphometry in guinea pigs acclimated to hypoxia during growth☆

Abstract

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Respir. Physiol.

Advan. Genetics

Respir. Physiol.

Quantitative lung morphology in Japanese waltzing mice

J. Appl. Physiol.

The effects of high altitude on adolescent growth in southern Peruvian Amerindians

Human Biol.

Lung elasticity and airway dynamics in Peruvian natives to high altitude

J. Appl. Physiol.

Deoxyribonucleic acid synthesis in lung cells during compensatory lung growth after pneumonectomy

Am. Rev. Resp. Dis.

Postnatal formation of alveoli: interstitial events and physiologic consequences

Effects of chronic exposure to cold or hypoxia on ventricular weights and ventricular myoglobin concentrations in guinea pigs during growth

Pflügers Arch.

The postnatal growth of the rat lung. III. Morphology

Anat. Rec.

The postnatal growth of the rat lung. I. Morphometry

Anat. Rec.

The adaptive response of the rat lung after bilobectomy

Am. Rev. Resp. Dis.