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The effects of the gamma-amino butyric acid (GABA) agonist baclofen applied directly on the nucleus of the tractus solitarius on the Hering-Breuer inspiratory-inhibitory and deflation reflexes were examined using anesthetized rats. Results reveal that baclofen attenuates but does not abolish these reflexes indicating that GABA receptors modulate the control of these reflexes.

A study of metabolic and ventilatory effects in newborn rabbits reveals that moderate hypoxia, which does not reduce the rabbit's sensitivity to oxygen deficiency, does not cause prolonged posthypoxic depression of body metabolism and ventilation. Moderate hypoxia enhances inhibitory neurotransmitter levels. Repeated hypoxia is conducive to respiratory system recovery which is essential for the survival of newborn rabbits.

A study of awake rats reveals that cocaine interaction with the dopaminergic system possibly causes the cocaine-induced respiratory excitation that is possibly linked with behavioral arousal. While acute cocaine possibly increases alveolar ventilation under conditions of hypoxia and hypercapnia, chronic cocaine may reduce peripheral chemosensitivity, thereby causing respiratory depression.

The effects of anoxia in extracellular concentrations of potassium ((K+)O) and calcium ((Ca2+)O) were studied in the medulla of newborn rabbits using ion-selective microelectrodes to monitor changes in the ion levels. Anoxia produced an age-dependent decrease in both (K+)O and (Ca2+)O resting concentrations in the brain stem confirming the neonatal brain's high resistance to oxygen deprivation.

Investigates the effects of acute and chronic cocaine on breathing and chemosensitivity in rats. Respiratory variables recorded during room air breathing before and after injection of sodium chloride or cocaine; Ventilatory variables during hypercapnia before and after cocaine injection; Effects of hypoxia.