Activity of pulmonary surfactant after blocking the associated proteins SP-A and SP-B.
To investigate the role of the pulmonary surfactant-associated proteins SP-A and SP-B, the respective monoclonal antibody (anti-A or anti-B) was added to porcine pulmonary surfactant at a weight ratio of 1:2, and the mixtures were tested on surfactant-deficient immature newborn rabbits (gestational age 26 days). Under pentobarbital sodium anesthesia and mechanical ventilation with a 25-cmH2O peak insufflation pressure, the tidal volumes of the animals given surfactant alone and of those given surfactant containing anti-A were 27.9 +/- 5.1 and 25.1 +/- 9.6 (SD) ml/kg, respectively, whereas that of those given surfactant with anti-B was 5.8 +/- 3.6 ml/kg (P less than 0.05). The surface adsorption times of surfactant alone and of anti-A-containing surfactant were less than 0.8 s compared with greater than 120 s (P less than 0.01) for anti-B-containing surfactant. The anti-B suppressed the surfactant activity until the weight ratio was decreased to 2:100. The role of SP-A could not be clarified, but it was concluded that SP-B is an essential factor for surfactant activity.
Department of Anesthesiology, School of Medicine, Kanazawa University, Japan.
T
T
Kobayashi
K
K
Nitta
R
R
Takahashi
K
K
Kurashima
B
B
Robertson
Y
Y
Suzuki
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D000911:Antibodies, Monoclonal; D001835:Body Weight / Q000187:drug effects; D004594:Electrophysiology; D015151:Immunoblotting; D008168:Lung / Q000502:physiology*; D010743:Phospholipids / Q000737:chemistry; D010991:Plethysmography; D011510:Proteolipids / Q000037:antagonists & inhibitors* / Q000276:immunology; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000037:antagonists & inhibitors* / Q000737:chemistry / Q000276:immunology / Q000502:physiology*; D011817:Rabbits; D012121:Respiration, Artificial; D012129:Respiratory Function Tests; D013499:Surface Properties; D013552:Swine
D000911:Antibodies, Monoclonal; D010743:Phospholipids; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants