Dopaminergic control of respiration as shown by effects of XXXX .

@entity1353 @entity935 @entity4774 @entity95 @entity1767 @entity2211 @entity973
The dopaminergic control of respiration in conscious and @entity4774 -anaesthetized @entity95 , was studied by comparing the respiratory effects of @entity973 alone (4-AP; 1 mg/kg i.v.) and those after the administration of @entity935 antagonists ( @entity2211 and @entity1767 ; 1 mg/kg each). The respiratory rate in conscious @entity95 was increased by 4-AP. After @entity2211 this increase was reduced and preceded by a transient decrease. In spontaneously @entity1353 , anesthetized @entity95 there was a transient reduction after which the respiratory rate was increased by 4-AP; tidal volume was affected in an inverse manner. After @entity2211 , the excitatory effect of 4-AP on respiratory rate and the inhibitory effect on tidal volume were blocked. The effects of 4-AP on respiratory rate were prevented by vagotomy. In anesthetized, vagotomized, paralyzed and artificially ventilated @entity95 (VPV animals) the peak amplitude of the integrated phrenic nerve activity ("phrenic activity') was increased by 4-AP. After pretreatment with @entity1767 this effect of 4-AP on phrenic activity was reduced while the respiratory rate was now increased. In VPV animals with denervated carotid bodies the excitatory effect of 4-AP on phrenic activity was strongly enhanced and respiratory rate was increased. These effects were slightly reduced but not blocked by @entity1767 . It is concluded that endogenous @entity935 is involved in the control of respiration through effects on peripheral mechanisms (inhibition of inspiratory activity and enhancement of respiratory rate) as well as on central mechanisms (stimulation of inspiratory activity and reduction of respiratory rate).
