Role of excitatory aminoacids in neonatal hypoglycemia.
BACKGROUND
In many neurological disorders, injury to neurons may be due in part to overstimulation of the receptors for the excitatory amino acids glutamate and aspartate. The same excitotoxic mechanism and high aspartate levels in experimental studies led to this study of the concentrations of glutamate and aspartate and zinc, copper, and magnesium levels in the cerebrospinal fluid (CSF) of hypoglycemic newborns.


METHODS
Aspartate and glutamate were determined by high-performance liquid chromatography, and magnesium, zinc and copper by atomic absorption spectrophotometer.


RESULTS
The CSF levels of aspartate (3.98 +/- 1.77 mumol/L) and glutamate (1.7 +/- 1.05 mumol/L) in 20 hypoglycemic newborns were significantly higher when compared with the values of aspartate (2.19 +/- 0.6 mumol/L) and glutamate (0.77 +/- 0.34 mumol/L) of 10 control newborns. In the hypoglycemic patients, the concentration of zinc (0.57 +/- 0.13 microgram/mL), but not copper (0.39 +/- 0.40 microgram/mL) was significantly lower when compared with the control values. There was no difference in the magnesium levels between the two groups.


CONCLUSIONS
The higher levels of excitatory amino acids found in the CSF of hypoglycemic infants than in controls were consistent with previous animal studies, which may indicate the role of excitatory amino acids in the late biochemical effects of hypoglycemia in newborn brain metabolism.
Aral
Y Z
YZ
Department of Pediatrics, Gazi University Medical Faculty, Ankara, Turkey.
Gücüyener
K
K
Atalay
Y
Y
Hasanoğlu
A
A
Türkyilmaz
C
C
Sayal
A
A
Biberoğlu
G
G
D001224:Aspartic Acid / Q000134:cerebrospinal fluid; D003300:Copper / Q000134:cerebrospinal fluid; D018846:Excitatory Amino Acids / Q000502:physiology*; D018698:Glutamic Acid / Q000134:cerebrospinal fluid; D006801:Humans; D007003:Hypoglycemia / Q000134:cerebrospinal fluid / Q000503:physiopathology*; D007231:Infant, Newborn; D008274:Magnesium / Q000134:cerebrospinal fluid; D015032:Zinc / Q000134:cerebrospinal fluid
D018846:Excitatory Amino Acids; D001224:Aspartic Acid; D018698:Glutamic Acid; D003300:Copper; D008274:Magnesium; D015032:Zinc