title: Effect of Tocolytics on Surfactant Secretion When Administered with Betamethasone: An in Vitro Study.
abstract: OBJECTIVE
  To analyze the amount of surfactant protein (SP)-B and lecithin/sphingomyelin (L/S) ratio in response to betamethasone (BMS) alone as compared with magnesium sulfate (Mg(2+)), indomethacin (Indo), and nifedipine (Nif) with or without BMS.
  
  
  METHODS
  NCI-H441 human lung cells were grown and distributed into eight plates. BMS and tocolytics were added and the final plates were: control, BMS only, and each tocolytic ± BMS. Cells were stained with SP-B antibodies and relative fluorescence was measured. Lipids were also extracted, identified, and examined for relative densities. The L/S ratio was calculated.
  
  
  RESULTS
  Nine independent measurements were obtained for each plate. The protein analysis revealed that among all eight plates, SP-B levels were highest among BMS only. There was a nonsignificant decrease in SP-B in each of the combinations of tocolytics + BMS as compared with BMS only. Compared with BMS only, L/S ratio was decreased in Mg(2+) + BMS (p = 0.041), Indo + BMS (p = 0.042), and Nif + BMS (p = 0.025).
  
  
  CONCLUSIONS
  In our in vitro human lung cell model, SP-B and L/S ratio increased in response to BMS administration alone. The addition of tocolytics to BMS resulted in no increase in L/S ratio and no changes seen in SP-B production compared with BMS alone.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, University of Texas Health Science Center at Houston, Houston, Texas.
authors.forename: Ziad A
authors.initials: ZA
authors.lastname: Haidar
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, University of Texas Health Science Center at Houston, Houston, Texas.
authors.forename: Baha M
authors.initials: BM
authors.lastname: Sibai
authors.affiliation: Department of Obstetrics and Gynecology, Miami Valley Hospital, Dayton, Ohio.
authors.forename: Jiri D
authors.initials: JD
authors.lastname: Sonek
authors.affiliation: Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, Ohio.
authors.forename: Shamili
authors.initials: S
authors.lastname: Sammohi
authors.affiliation: Department of Obstetrics and Gynecology, Miami Valley Hospital, Dayton, Ohio.
authors.forename: David S
authors.initials: DS
authors.lastname: Mckenna
authors.affiliation: Department of Pharmacology and Toxicology, Boonshoft School of Medicine, Wright State University, Dayton, Ohio.
authors.forename: William C
authors.initials: WC
authors.lastname: Grunwald
authors.affiliation: Department of Obstetrics and Gynecology, Miami Valley Hospital, Dayton, Ohio.
authors.forename: David R
authors.initials: DR
authors.lastname: Cool
mesh_terms: D001623:Betamethasone / Q000494:pharmacology*; D002460:Cell Line; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology; D054709:Lecithins / Q000378:metabolism*; D008168:Lung / Q000166:cytology; D008278:Magnesium Sulfate / Q000494:pharmacology; D009543:Nifedipine / Q000494:pharmacology; D037701:Pulmonary Surfactant-Associated Protein B / Q000187:drug effects* / Q000378:metabolism; D013109:Sphingomyelins / Q000378:metabolism*; D015149:Tocolytic Agents / Q000494:pharmacology*
chemical_list: D005938:Glucocorticoids; D054709:Lecithins; D037701:Pulmonary Surfactant-Associated Protein B; D013109:Sphingomyelins; D015149:Tocolytic Agents; D008278:Magnesium Sulfate; D001623:Betamethasone; D009543:Nifedipine; D007213:Indomethacin