Document Detail


Dopamine, dobutamine, and phentolamine effects on pulmonary vascular mechanics.
MedLine Citation:
PMID:  6863087     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The pressure-flow (P-Q) relationship of the pulmonary vasculature, in an isolated canine lobe perfused under classical zone II conditions, can be characterized by a rectilinear segment at high flow, a curvilinear segment at low flow, and a pulmonary arterial pressure (Ppa) that exceeds alveolar pressure at zero flow. This demonstrates the presence of critical closure in the pulmonary vascular bed. Effects of drugs on pulmonary vascular resistance (PVR) must take the normal P-Q relationship into account. We examined the effect of dopamine (D) and dobutamine (DB), alone and in combination with phentolamine (P), on the slope of the rectilinear segment of the P-Q curve (equivalent to vascular conductance), the extrapolated Ppa intercept (Ppai), and the Ppa at zero flow (Ppaz). Low-dose D (0.4-0.8 mg) and DB (1.0-5.0 mg) did not significantly alter any parameter from control. Higher-dose D (1.2-6.8 mg) and DB (13-38 mg) decreased vascular conductance 32.3 +/- 12.1 (SE) to 50.45 +/- 5.6% (P less than 0.05), and P alone increased conductance 12.0 +/- 2.6% (P less than 0.01) from control with no significant effect on Ppai or Ppaz. The change in conductance with D and DB alone was abolished when either drug was given in combination with P. Ppaz and Ppai decreased significantly from control with DB in combination with P when no significant effect on vascular conductance was noted. The results suggest that lung vessels determining changes in flow resistance are pharmacologically distinct from those subserving critical closure in the pulmonary vascular bed.
Authors:
R Graham; C Skoog; W Macedo; J Carter; L Oppenheimer; J Rabson; H S Goldberg
Related Documents :
775627 - Pulmonary vein flow pattern in man during thoracotomy.
19619697 - Correlation of impedance cardiography with invasive hemodynamic measurements in patient...
6148467 - Vasodilator therapy for primary pulmonary hypertension.
8442587 - Neuronal m2 muscarinic receptor function in guinea-pig lungs is inhibited by indomethacin.
1915687 - Posture and the circulation: the age effect.
3246197 - Beat-to-beat blood pressure response in asymptomatic iddm subjects.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of applied physiology: respiratory, environmental and exercise physiology     Volume:  54     ISSN:  0161-7567     ISO Abbreviation:  J Appl Physiol     Publication Date:  1983 May 
Date Detail:
Created Date:  1983-08-11     Completed Date:  1983-08-11     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  7801242     Medline TA:  J Appl Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1277-83     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Blood Pressure / drug effects
Blood Volume / drug effects
Catecholamines / pharmacology*
Dobutamine / pharmacology*
Dogs
Dopamine / pharmacology*
Dose-Response Relationship, Drug
Female
Lung / blood supply*
Male
Perfusion
Phentolamine / pharmacology*
Regional Blood Flow / drug effects
Vascular Resistance / drug effects
Chemical
Reg. No./Substance:
0/Catecholamines; 34368-04-2/Dobutamine; 50-60-2/Phentolamine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Respiratory movements of the vocal cords.
Next Document:  Secretion of Weibel-Palade bodies observed in extra-alveolar vessels of rabbit lung.