Hypoxic-ischemic encephalopathy (HIE) is the result of a chain of events ca
used mainly by cytokines and nitric oxide (NO) release, which is later on f
ollowed by free oxygen radical injury. To investigate NO involvement in asp
hyxiated newborns, serum and cerebrospinal fluid (CSF) values of NO levels
in 17 neonates with HIE were detected. Infants at or above 37 weeks of gest
ation were classified to have mild, moderate and severe HIE due to Sarnat a
nd Sarnat. Samples obtained between 24 and 72 h of life were immediately fr
ozen at -70 degrees C till the time of measurement by Sievers NOA. Five pat
ients had mild, 6 patients had moderate and 6 patients had severe HIE, 4 in
the severe HIE group also had multisystem involvement. The CSF NO levels w
ere significantly higher in moderate and severe HIE groups compared to the
mild HIE group (p = 0.028 and p = 0.018 respectively). Our results show tha
t NO level increases in CSF with the severity of HIE between 24 and 72 h fo
llowing asphyxia. According to the animal work, this is the time period whe
re inducible NO synthase gets activated and could cause neurotoxicity, whic
h might perhaps be prevented by interventions.