Role of adenosine in the hypoxic ventilatory response of the newborn piglet

Autor: Lopes Jm, G. M. Davis, Jacob V. Aranda, K. Mullahoo
Rok vydání: 1994
Předmět:
Zdroj: Pediatric Pulmonology. 17:50-55
ISSN: 1099-0496
8755-6863
DOI: 10.1002/ppul.1950170109
Popis: The role of intracerebral adenosine levels in the control of ventilatory response to hypoxia was explored in 15 spontaneously breathing intubated piglets, 1-5 days old, sedated with chloral hydrate. Respiration was recorded via by a pneumotachograph. In all animals exposed to hypoxia (12% O2) for 10 minutes. There was an initial increase in ventilation followed by a late decrease (the biphasic ventilatory response). Both intravenous caffeine citrate (20 mg/kg) and an FiCO2 of 0.05 separately abolished or attenuated the late ventilatory depression associated with hypoxia. In the same piglets, the administration of 10 micrograms dipyridamole, a competitive inhibitor of adenosine receptors, directly into the cerebral ventricles abolished the hyperventilatory response to hypoxia. Conversely, the use of 20 micrograms intraventricular 8-phenyltheophylline abolished the late ventilatory depression associated with hypoxia. Neither drug had a direct effect on ventilation at the time of injection. These results suggest that adenosine is a part of the diphasic ventilatory response to hypoxia.
Databáze: OpenAIRE