Ragweed sensitization alters pulmonary vascular responses to bronchoprovocation in beagle dogs.
In ragweed (RW)-sensitized beagle dogs, we tested the hypothesis that reactivity of the pulmonary vasculature was enhanced with aerosolized histamine (Hist) and RW. Seven dogs were neonatally sensitized with repeated intraperitoneal RW injections, and 12 dogs were controls (Con). The dogs were anesthetized with intravenous chloralose, mechanically ventilated, and instrumented with femoral arterial and pulmonary artery catheters. Specific lung compliance (CLsp), specific lung conductance (Gsp), systemic vascular resistance index, and pulmonary vascular resistance index (PVRI) were measured before and after bronchoprovocation with Hist and RW. After Hist inhalation (5 breaths of 30 mg/ml), both Con and RW dogs had significant (P < 0.05) decreases in CLsp (-51 +/- 4 and -53 +/- 5%, respectively) and Gsp (-65 +/- 5 and -69 +/- 3%, respectively), but only RW-sensitized dogs had a significant increase in PVRI (38 +/- 10%). After RW inhalation (60 breaths of 0.8 mg/ml), only RW-sensitized dogs had significant increases (62 +/- 20%) in PVRI and decreases in Gsp (-77 +/- 4%) and CLsp (-65 +/- 7%). We conclude that, compared with Con, RW-sensitized beagle dogs have increased pulmonary vasoconstrictive responses with Hist or RW inhalation.
Theodorou
A
A
Respiratory Sciences Center and Steele Memorial Children's Research Center, University of Arizona, Tucson, Arizona 85724-5073, USA.
Weger
N
N
Kunke
K
K
Rhee
K
K
Bice
D
D
Muggenberg
B
B
Lemen
R
R
D000485:Allergens / Q000276:immunology*; D000818:Animals; D000831:Animals, Newborn; D001784:Blood Gas Analysis; D001835:Body Weight / Q000502:physiology; D001985:Bronchial Provocation Tests; D002302:Cardiac Output / Q000502:physiology; D004285:Dogs; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006632:Histamine / Q000494:pharmacology; D008170:Lung Compliance / Q000502:physiology; D008297:Male; D011058:Pollen / Q000276:immunology*; D011652:Pulmonary Circulation / Q000502:physiology*; D012129:Respiratory Function Tests; D012130:Respiratory Hypersensitivity / Q000097:blood / Q000276:immunology / Q000503:physiopathology*; D014655:Vascular Resistance / Q000502:physiology
D000485:Allergens; D006632:Histamine