Ventilatory Response to Hypoxia and Tolerance to High Altitude in Women: Influence of Menstrual Cycle, Oral Contraception, and Menopause

Adaptation or natural acclimatization results from the interaction between genetic variations and acclimatization resulting in individuals with ability to live and reproduce without problems at high altitudes. Testosterone is a hormone that increases erythropoiesis and inhibits ventilation. It could therefore, be associated to the adaptation to high altitudes. Excessive erythrocytosis, which in turn will develop chronic mountain sickness is caused by low arterial oxygen saturation and ventilatory inefficiency and blunted ventilatory response to hypoxia. Testosterone is elevated in natives at high altitude with excessive erythrocytosis (>21 g /dl hemoglobin in men and >19 g/dl in women). Natives from the Peruvian central Andes with chronic mountain sickness express gene SENP1 that enhances the activity of the androgen receptor. Results of the current investigations suggest that increase in serum testosterone and hemoglobin is not adequate for adaptation to high altitude.

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Selected Contribution: High-altitude natives living at sea level acclimatize to high altitude like sea-level natives

Journal of Applied Physiology ◽

10.1152/japplphysiol.00857.2002 ◽

2003 ◽

Vol 94 (3) ◽

pp. 1263-1268 ◽

Cited By ~ 6

Author(s):

Maria Rivera-Ch ◽

Alfredo Gamboa ◽

Fabiola León-Velarde ◽

Jose-Antonio Palacios ◽

David F. O'Connor ◽

...

Keyword(s):

High Altitude ◽

Sea Level ◽

Time Course ◽

Ventilatory Response ◽

Air Breathing ◽

High Altitude Natives ◽

End Tidal ◽

Ventilatory Response To Hypoxia

Sea-level (SL) natives acclimatizing to high altitude (HA) increase their acute ventilatory response to hypoxia (AHVR), but HA natives have values for AHVR below those for SL natives at SL (blunting). HA natives who live at SL retain some blunting of AHVR and have more marked blunting to sustained (20-min) hypoxia. This study addressed the question of what happens when HA natives resident at SL return to HA: do they acclimatize like SL natives or revert to the characteristics of HA natives? Fifteen HA natives resident at SL were studied, together with 15 SL natives as controls. Air-breathing end-tidal Pco 2 and AHVR were determined at SL. Subjects were then transported to 4,300 m, where these measurements were repeated on each of the following 5 days. There were no significant differences in the magnitude or time course of the changes in end-tidal Pco 2 and AHVR between the two groups. We conclude that HA natives normally resident at SL undergo ventilatory acclimatization to HA in the same manner as SL natives.

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Ventilatory response to hypoxia and hypercapnia in cats living at high altitude

Journal of Applied Physiology ◽

10.1152/jappl.1969.27.6.834 ◽

1969 ◽

Vol 27 (6) ◽

pp. 834-836 ◽

Cited By ~ 10

Author(s):

T. F. Hornbein ◽

S. C. Sorensen

Keyword(s):

High Altitude ◽

Ventilatory Response ◽

Ventilatory Response To Hypoxia

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Changes in the Carotid Body and the Ventilatory Response to Hypoxia in Chronically Hypoxic Rats

Clinical Science ◽

10.1042/cs0500311 ◽

1976 ◽

Vol 50 (4) ◽

pp. 311-313 ◽

Cited By ~ 14

Author(s):

Gwenda R. Barer ◽

C. W. Edwards ◽

Angela I. Jolly

Keyword(s):

High Altitude ◽

Carotid Body ◽

Ventilatory Response ◽

Littermate Control ◽

Young Rats ◽

Carotid Bodies ◽

Ventilatory Response To Hypoxia

1. Young rats were kept in a hypoxic chamber for 2–11 weeks and compared with littermate control animals. 2. The carotid bodies of the hypoxic rats enlarged, resembling those of men and animals living at high altitude. 3. Permanent blunting of the ventilatory response to hypoxia did not occur. Immediately on removal from the chamber, the rats, lightly anaesthetized, showed a smaller increase in ventilation during hypoxia than did control animals but this difference disappeared after 3 days' recovery in normoxia.

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