Cardiovascular responses in the sea raven, Hemitripterus americanus, XXXX .

@entity1169 @entity63247 @entity101 @entity2850 @entity591 @entity2507 @entity3302 @entity3897 @entity551 @entity1168 @entity65
Increases in the water pressure (PW) around the trunk of the sea raven (Hemitripterus americanus Gmelin) were used to evaluate the effects of @entity2850 on cardiovascular variables. Cardiac output (Vb), heart rate (fH) and blood pressures in the ventral aorta, dorsal aorta and ductus Cuvier (Pva, Pda and @entity63247 , respectively) were measured. A 20 cm @entity2507 increase in PW decreased vascular conductance by up to 25%. During @entity2850 , a reflex @entity1168 reduced Vb and attenuated the accompanying @entity551 . Pretreatment of the fish with the sympathetic antagonist, @entity1169 , further attenuated the @entity101 by accentuating the reflex @entity1168 . Subsequent pretreatment with @entity3302 , a vascular smooth muscle poison, potentiated these effects and did not reveal any autoregulatory vasodilation in the periphery. @entity3897 pretreatment completely abolished the reflex @entity1168 , indicating that the @entity1168 resulted from increased vagal cholinergic tone. The fish also exhibited @entity65 during the 2 min @entity2850 . An accommodation of the barostatic reflex (reduced vagal tone) and a sympathetic @entity591 raised Vb and passively increased vascular conductance. The set point for the barostatic @entity1168 was apparently temperature-sensitive.
