Inhaled nitric oxide increases surfactant protein gene expression in the intact lamb.
Inhaled nitric oxide (iNO) is used to treat a number of disease processes. Although in vitro data suggest that nitric oxide (NO) alters surfactant protein gene expression, the effects in vivo have not been studied. The objective of this study was to evaluate the effects of iNO on surfactant protein (SP)-A, -B, and -C gene expression in the intact lamb. Thirteen 4-wk-old lambs were mechanically ventilated with 21% oxygen and received iNO at 40 ppm (n = 7) or vehicle gas (n = 6) for 24 h. Peripheral lung biopsies were obtained at 0, 12, and 24 h and analyzed for surfactant mRNA, protein, and total DNA content. Inhaled NO increased SP-A and SP-B mRNA content by 80% from 0 to 12 h and by 78 and 71%, respectively, from 0 to 24 h. There was an increase in SP-A and SP-B protein content by 45% from 0 to 12 h, and a decrease by 70 and 65%, respectively, from 0 to 24 h. DNA content was unchanged. The mechanisms and physiological effects of these findings warrant further investigation.
Stuart
Regan B
RB
Dept. of Pediatrics, Univ. of California, San Francisco, 505 Parnassus M680, Box 0106, San Francisco, California 94143-0106, USA. rstuart@itsa.ucsf.edu
Ovadia
Boaz
B
Suzara
Vincent V
VV
Ross
Patrick A
PA
Thelitz
Stephan
S
Fineman
Jeffrey R
JR
Gutierrez
Jorge A
JA
D000280:Administration, Inhalation; D000818:Animals; D004247:DNA / Q000032:analysis; D015870:Gene Expression / Q000187:drug effects; D009569:Nitric Oxide / Q000494:pharmacology*; D011652:Pulmonary Circulation / Q000187:drug effects; D037662:Pulmonary Surfactant-Associated Protein A / Q000235:genetics; D037701:Pulmonary Surfactant-Associated Protein B / Q000235:genetics; D037721:Pulmonary Surfactant-Associated Protein C / Q000235:genetics; D037661:Pulmonary Surfactant-Associated Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D020545:Respiratory Mucosa / Q000187:drug effects* / Q000502:physiology*; D012756:Sheep
D037662:Pulmonary Surfactant-Associated Protein A; D037701:Pulmonary Surfactant-Associated Protein B; D037721:Pulmonary Surfactant-Associated Protein C; D037661:Pulmonary Surfactant-Associated Proteins; D012333:RNA, Messenger; D009569:Nitric Oxide; D004247:DNA