Yoshikazu Sakakibara

Lack of positive interaction between CO2 and hypoxic stimulation for PCO2–VAS response slope in humans

To compare the effect of hypoxia on ventilatory responses and respiratory sensation to carbon dioxide, 29 young adults were examined using a modified Reads rebreathing method with four experimental conditions. We used varying gas mixtures and kept PET(O2) constant at >300, 100, 80 and 60 mmHg for each four rebreathing tests. Respiratory sensation was measured by visual analog scale (VAS). The slope of the CO2-ventilation response curve increased significantly with hypoxia, confirming a positive ventilatory interaction between hypoxia and hypercapnia. However, the slope of the CO2-VAS response curve remained unchanged. The V(E)-VAS relation slope tended to become depressed with advancing hypoxia, i.e. the magnitude of VAS elicited by a given ventilation decreased with hypoxia, signifying that dyspneic sensation was effectively mitigated during hypoxic hyperventilation. We suggest that this relief of dyspneic sensation might be due to the inhibitory respiratory effect from augmented pulmonary stretch receptor (PSR) activity.

Central Hypoxic-Hypercapnic Interaction in Mild Hypoxia in Man

AbstractHypoxic-hypercapnic interaction in mild hypoxia was studied in 12 healthy males. Steady state ventilatory responses to hypercapnic-hypoxia

Relationship Between Ventilatory and Circulatory Responses to Sustained Mild Hypoxia in Humans

\left[ {\Delta \dot V_{\left( {\text{s}} \right)} } \right]

Ventilatory vs. dyspneic responses to augmenting and subsequently declining CO2 stimulation in humans.

were obtained as the difference in ventilation between hypoxia (mean values ± S.D. of

Different profile in ventilatory vs. respiratory sensation responses to CO2 with varying Po2.

P_{{\text{ET}}_{{\text{O}}_{\text{2}} } }

Serial Changes in Acute Hypoxic and Hypercapnic Ventilatory Responses during High Altitiude Acclimatization

=7.36±0.20 kPa or of