Effects of glucagon on in vitro liquid production by lungs from fetal guinea pigs
N Choo, A L Liu, A M Perks
Departments of
Obstetrics and Gynecology and Zoology, University of British Columbia,
Vancouver, BC, Canada V6H 3V5
Correspondence to: Dr Perks, Department of Obstetrics and Gynecology, Faculty of Medicine, Room 2H30, 4490 Oak Street, Vancouver, BC, Canada V6H 3V5
Accepted 17 November
1999
BACKGROUND
Lung liquid
reabsorption in newborns with respiratory distress syndrome can be
deficient. Respiratory distress syndrome is often seen in infants of
diabetic mothers, in whom the neonatal surge of glucagon is suppressed.
AIMTo investigate the
possible effects of glucagon on lung liquid reabsorption.
METHODSLungs from
near term fetal guinea pigs (62 (2) days gestation; term = 67 days)
were supported in vitro for three hours; lung liquid production and
reabsorption were monitored by a dye dilution method.
RESULTSUntreated
control preparations produced fluid at 1.75 (0.33) ml/h per kg body
weight, and did not change significantly in three hours; those immersed
in 10
12 M glucagon during the middle hour showed no
significant change, but those given higher concentrations all showed
significant reductions in fluid production or even reabsorption (65.6 (10.3)% fall at 1011 M, 70.0 (6.3)% fall at
1010 M, and 90.6 (11.1)% fall at 109 M;
based on 54 preparations). At 109 M glucagon, 12 out of
30 preparations reabsorbed fluid. The linear log dose-response curve
(r2 = 0.94) gave a theoretical
threshold at 4 × 1015 M glucagon. Responses appeared
to involve the amiloride sensitive Na+ based reabsorptive
system: responses to 109 M glucagon appeared to be
reduced by 106 M amiloride, and were abolished by
105 M amiloride (based on 72 preparations).
CONCLUSIONSThe
results suggest that the surge of glucagon at birth may help to drain
the lungs of fluid. As glucagon liberates cAMP, which also stimulates
surfactant, glucagon is worth consideration for possible use in
neonatal respiratory distress.
Keywords: glucagon; fetus; lung liquid; guinea pig; respiratory distress syndrome
© 2000 by Archives of Disease in Childhood
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
-
Cassin, S., Perks, A. M.
(2002). Estimation of lung liquid production in fetal sheep with blue dye dextran and radioiodinated serum albumin. J. Appl. Physiol.
92: 1531-1538
[Abstract] [Full Text]
- Full Text
- Full Text (PDF)
- Submit a response
- Alert me when this article is cited
- Alert me when eLetters are posted
- Alert me if a correction is posted
- Citation Map
Services
- Email this link to a friend
- Similar articles in ADC Online
- Similar articles in PubMed
- Add article to my folders
- Download to citation manager
- Request Permissions
Citing Articles
Google Scholar
PubMed
Topic Collections
Bookmark with
Register for free content
The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.
Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.
