TY - JOUR
T1 - Stimulation of the dopamine 1 receptor increases lung edema clearance
AU - Barnard, Michele L.
AU - Ridge, Karen M.
AU - Saldias, Fernando
AU - Friedman, Eliot
AU - Gare, Meir
AU - Guerrero, Carmen
AU - Lecuona, Emilia
AU - Bertorello, Alejandro M.
AU - Katz, Adrian I.
AU - Sznajder, Jacob I.
PY - 1999
Y1 - 1999
N2 - We previously reported that lung edema clearance was stimulated by dopamine (DA). The purpose of this study was to determine whether the DA- mediated stimulation of edema clearance occurs via an adrenergic or dopaminergic regulation of alveolar epithelial Na, K-ATPase. When isolated perfused rat lungs were coinstilled with DA and SCH 23390 (a specific D1 receptor antagonist), there was a dose-dependent attenuation of the stimulatory effects of DA. Coinstillation with S-sulpiride (a specific D2 receptor antagonist) or propranolol (a β-adrenergic antagonist) did not alter DA-stimulated clearance. Similarly, the specific dopaminergic D1 agonist fenoldopam increased lung edema clearance, but quinpirole (a specific dopaminergic D2 agonist) did not. 125I-SCH 23982 binding studies suggested that D1 receptors are expressed on alveolar type II (ATII) cells with an apparent dissociation constant (K(d)) of 4.4 nM and binding maximum (Bmax) 9.8 pmol/mg. Consistent with these results, the D1 receptor messenger RNA (mRNA) and protein were detected in ATII cells by reverse transcriptase- polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. These data demonstrate a novel mechanism involving the activation of dopaminergic D1 receptors which mediates DA-stimulated edema removal from rat lungs.
AB - We previously reported that lung edema clearance was stimulated by dopamine (DA). The purpose of this study was to determine whether the DA- mediated stimulation of edema clearance occurs via an adrenergic or dopaminergic regulation of alveolar epithelial Na, K-ATPase. When isolated perfused rat lungs were coinstilled with DA and SCH 23390 (a specific D1 receptor antagonist), there was a dose-dependent attenuation of the stimulatory effects of DA. Coinstillation with S-sulpiride (a specific D2 receptor antagonist) or propranolol (a β-adrenergic antagonist) did not alter DA-stimulated clearance. Similarly, the specific dopaminergic D1 agonist fenoldopam increased lung edema clearance, but quinpirole (a specific dopaminergic D2 agonist) did not. 125I-SCH 23982 binding studies suggested that D1 receptors are expressed on alveolar type II (ATII) cells with an apparent dissociation constant (K(d)) of 4.4 nM and binding maximum (Bmax) 9.8 pmol/mg. Consistent with these results, the D1 receptor messenger RNA (mRNA) and protein were detected in ATII cells by reverse transcriptase- polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. These data demonstrate a novel mechanism involving the activation of dopaminergic D1 receptors which mediates DA-stimulated edema removal from rat lungs.
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U2 - 10.1164/ajrccm.160.3.9812003
DO - 10.1164/ajrccm.160.3.9812003
M3 - Article
C2 - 10471628
AN - SCOPUS:0032827429
SN - 1073-449X
VL - 160
SP - 982
EP - 986
JO - American journal of respiratory and critical care medicine
JF - American journal of respiratory and critical care medicine
IS - 3
ER -