Hematologic Observations on the Yak

Adams, William; Graves, I. L.; Pyakural, S.

doi:10.3181/00379727-148-38613

Cited by 6 publications

(5 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In agreement with previous observations at high altitude (1,6), we observed that the levels of Hb and Hct of pikas were lower than those of rats. Lower Hb and Hct values at high altitude, which can be a feature of residence at high altitude and may be regarded as evidence of genetic adaptation to high altitude (6), may function to maintain blood viscosity and pulmonary vascular resistance at low levels.…”

Section: H1795 Pulmonary Circulation In An Indigenous Mountain Animalsupporting

confidence: 93%

“…Bullard (11) pointed out that successful adaptation to high altitude in these animals does not involve an increase in the concentration of 2,3-DPG. The levels of 2,3-DPG in high-altitude animals are extremely low or absent in contrast to those of unadapted animals, as previously reported by Adams et al (1) and Chiodi (13). Our results are similar to these observations in that the 2,3-DPG level in the pikas was significantly lower than that of the rats, indicating increased affinity of Hb for oxygen in the pikas, which may reflect successful adaptation to high altitude.…”

Section: H1795 Pulmonary Circulation In An Indigenous Mountain Animalsupporting

confidence: 90%

See 1 more Smart Citation

Blunted hypoxic pulmonary vasoconstrictive response in the rodentOchotona curzoniae(pika) at high altitude

Kubo

Kobayashi

et al. 1998

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

To investigate the possible mechanisms of adaptation to chronic hypoxia in the pulmonary circulation, we made direct measurements of pulmonary arterial pressure (Ppa) in 10 awake pika rodents that were transported to Xining, People’s Republic of China (altitude 2,260 m) after being captured at 4,300 m and in 10 Wistar rats in a decompression chamber (simulated altitudes of 4,300 and 5,000 m) in Xining. Ppa was obtained at 1 h of exposure to each simulated altitude. The histology and immunohistochemistry of the lung tissues were also studied. Ppa in the pikas after the 4,300- and 5,000-m altitude exposures did not significantly increase, whereas in the rats Ppa rose significantly. Mean changes in Ppafrom 2,260 to 4,300 and 5,000 m were 1.48 ± 0.49 and 4.80 ± 0.67 mmHg in the pikas and 10.38 ± 3.36 and 19.10 ± 2.28 mmHg in the rats. The ratio of right ventricular to left ventricular plus septal weight in the pikas and rats was 0.22 and 0.45, respectively. The pikas maintained levels of Hb, hematocrit, and 2,3-diphosphoglycerate lower than those of the rats. The percent wall thickness of the small pulmonary arteries in the pikas and rats was 9.22 and 27.21%, respectively, and it was well correlated with the degree of Ppa in both groups. Mast cells were observed in the lungs of the rats (7.1 ± 0.33 cells/mm2) but not in the pikas. There was highly positive staining for mast cell tryptase and transforming growth factor-β around pulmonary vessels in the rats, whereas no demonstrable reaction was observed in the pikas. We conclude that the pika has adapted to high altitude by losing hypoxic pulmonary vasoconstriction and thin-walled pulmonary arterioles.

show abstract

Section: H1795 Pulmonary Circulation In An Indigenous Mountain Animalsupporting

confidence: 93%

Section: H1795 Pulmonary Circulation In An Indigenous Mountain Animalsupporting

confidence: 90%

Blunted hypoxic pulmonary vasoconstrictive response in the rodentOchotona curzoniae(pika) at high altitude

Kubo

Kobayashi

et al. 1998

American Journal of Physiology-Heart and Circulatory Physiology

View full text Add to dashboard Cite

show abstract

“…Of the four animals investigated, three had β" and only one had both β 1 -and "-chains. Adam et al' 26 ' found only one type of -chain in the hemoglobin from five yaks. Probably the frequency of occurence of the β π -chain is much higher than that of the !…”

Section: Discussionmentioning

confidence: 99%

Studies on Yak Hemoglobin(Bos grunniens,Bovidae): Structural Basis for High Intrinsic Oxygen Affinity?

Lalthantluanga¹,

Wiesner²,

Braunitzer³

1985

Biological Chemistry Hoppe-Seyler

View full text Add to dashboard Cite

Two types of alpha- and two types of beta-chains are found in the hemoglobin of yak population. The complete amino-acid sequences of the four polypeptide chains were determined. The two alpha-chains differ by two and the two beta-chains by three amino-acid substitutions. The substitution of valine at position 135 in the beta II-chain may be responsible for the high intrinsic oxygen affinity of yak hemoglobin.

show abstract

“…Greater blood O 2 -binding affinity is a very common, putatively adaptive mechanism that is well documented in native high-altitude species with genetic variants that underlie Hb-O 2 binding affinity, such as deer mice (Storz et al 2009(Storz et al , 2010Natarajan et al 2013) and hummingbirds (Projecto-Garcia et al 2013). In addition, increased blood O 2 -binding affinity has been reported in Andean llama, vicuña (Hall et al 1936), chinchillas and guinea-pigs , yak and pika on the Tibetan Plateau (Adams et al 1975;Ge et al 1998). Previous work indicates how low P 50 at altitude may be beneficial at high altitude (Eaton et al 1974;Hebbel et al 1978).…”

Section: Significancementioning

confidence: 97%

Increased blood‐oxygen binding affinity in Tibetan and Han Chinese residents at 4200 m

Simonson

Guan²,

Wagner

et al. 2014

Experimental Physiology

View full text Add to dashboard Cite

High-altitude natives are challenged by hypoxia and a potential compensation could be reduced blood P50, as seen in several high-altitude mammalian species. In 21 Qinghai Tibetan males and 9 Han Chinese, all resident at 4200 m, standard P50 was calculated from measurements of arterial PO2 and forehead oximeter oxygen saturation (SpO2), which was validated in a separate examination of 13 healthy sea-level subjects. In both Tibetans and Han Chinese, standard P50 was 24.5 (± 1.4 and 2.0 mmHg, respectively) and was lower than in the sea-level subjects (26.2 ± 0.6 mm Hg, p < 0.01). There was no relationship between P50 and [Hb] (the latter ranging from 15.2 and 22.9 g/dl in Tibetans). During peak exercise, P50 was not associated with alveolar-arterial PO2 difference or VO2/kg. There appears to be no apparent benefit of a lower P50 in this adult high-altitude Tibetan population.

show abstract

Hematologic Observations on the Yak

Cited by 6 publications

References 4 publications

Blunted hypoxic pulmonary vasoconstrictive response in the rodentOchotona curzoniae(pika) at high altitude

Blunted hypoxic pulmonary vasoconstrictive response in the rodentOchotona curzoniae(pika) at high altitude

Studies on Yak Hemoglobin(Bos grunniens,Bovidae): Structural Basis for High Intrinsic Oxygen Affinity?

Increased blood‐oxygen binding affinity in Tibetan and Han Chinese residents at 4200 m

Contact Info

Product

Resources

About