ISSN:
1432-136X
Keywords:
Ventilation
;
Central pattern generator
;
$$P_{O_2 }$$
;
Apnea
;
Hypoxia
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary 1. The response of the isolated crab ventilatory central pattern generator (CPG) to changes in oxygen tension was examined. The ventilatory rate increased and motor neuron burst durations decreased as oxygen tension ( $$P_{O_2 }$$ ) was increased from hypoxic to hyperoxic levels. The number of spikes per motor neuron burst, and intraburst phase relationships, were relatively insensitive to $$P_{O_2 }$$ . 2. Pauses in ventilation (apnea) were a common occurence at elevated $$P_{O_2 }$$ , but were rarely seen under hypoxic conditions. During prolonged periolds of apnea, hypoxia was an effective stimulus for eliciting the ventilatory rhythm, although hypoxia depresses the ventilatory rate. 3. Transient (〈3 min) increases in ventilatory rate follow steps from higher to lower levels of $$P_{O_2 }$$ ; longer compensatory increases (〉5 min) occur upon return to normoxia or hyperoxia following prolonged exposure to hypoxia. 4. The latencies for changes in the rate of ventilation in the isolated thoracic ganglion are much longer (3–5 min) than those observed in intact crustaceans following similar changes in $$P_{O_2 }$$ , supporting the view that peripheral oxygen receptors may help to mediate in vivo responses to changes in oxygen tension.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00692680
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