Key result
L-NAME reduces fetal DA caliber ~57% in immature rats, whereas indomethacin constricts near-term fetuses.
Why the study?
The role of nitric oxide in regulating ductus arteriosus patency during various fetal stages was unclear.
Does inhibition of nitric oxide synthase or cyclooxygenase differentially affect ductus arteriosus caliber in fetal rats at various gestational stages?
Population
Fetal rats at gestational days 17 to 21
Comparison
L-NAME (NOS inhibitor) vs indomethacin (cyclooxygenase inhibitor)
Design
Preclinical study with rapid-freezing and shaving methods
Follow-up
3 hours before cesarean section
Authors
Loading...
NO predominates over prostaglandins in maintaining early fetal rat DA patency; hypothesis-generating for stage-specific human PDA mechanisms.
Does inhibition of nitric oxide synthase or cyclooxygenase differentially affect ductus arteriosus caliber in fetal rats at various gestational stages?
p-value: p=<0.01
Endogenous nitric oxide plays a major role in maintaining ductus arteriosus patency in early fetal stages, while prostaglandins are more important near term.
Takizawa et al. (2000) studied Ductus arteriosus patency (n=340). L-NAME and Indomethacin vs. Untreated controls was evaluated on Caliber of the ductus arteriosus (DA) (p=<0.01). L-NAME caused marked constriction of the fetal ductus arteriosus in 19-day-old and immature rat fetuses (to 43% of control), whereas indomethacin caused marked constriction in near-term fetuses.
Synapse has enriched 4 closely related papers on similar clinical questions. Consider them for comparative context: