Role of dopamine in the peripheral mechanisms of respiration control

Under clinical conditions, we studied the interaction between dopamine (DA) metabolism and hypoxia stimulationrelated ventilatory responses (HVR) before and after adaptation to periodical hypoxic episodes. Thirty-seven young and elder persons were tested; among elder tested subjects there were patients with Parkinson’s desease treated or not treated with DOPA-DA precursor-containing drugs (levoDOPA/carbiDOPA). We measured the HVR indices and DA and DOPA contents in the venous blood of tested persons before and after a 14-day-long hypoxic training. The highest indices of the ventilation sensitivity to hypoxia together with the lowest above-mentioned chemical indices were observed in young persons. An increase in the DA and DOPA levels in the venous blood were observed concurrently with suppression of the ventilation responses to hypoxic episodes. After a course of periodical hypoxic sessions, we observed in all groups opposite dynamics of DA and DOPA metabolism. An increase in the DA level in young persons and a trend toward its decrease in older healthy persons and parkinsonian patients was nevertheles accompanied by an HVR increase in all groups. Possible relations between the DA metabolism indices and peripheral mechanisms of respiratory control are discussed.