title: Correlation of plasma hypoxanthine and catecholamine levels in the umbilical vein.
abstract: Hypoxanthine and the catecholamines, dopamine, norepinephrine and epinephrine were determined in umbilical venous cord plasma in 27 term babies delivered vaginally. When correlating hypoxanthine with log epinephrine a weak positive linear correlation was found (r = 0.45, p less than 0.05). The correlation between hypoxanthine and log dopamine showed a significant negative linear correlation (r = -0.65, p less than 0.01). There was also a significant correlation between log epinephrine and pH (r = 0.72, P less than 0.01) and base deficit (r = 0.46, P less than 0.05). In four babies who suffered intrauterine hypoxia, hypoxanthine was significantly elevated compared with non hypoxic babies (21.4 +/- 5.1 versus 6.3 +/- 6.6 mumol/l, P less than 0.01). In these babies norepinephrine (3710 +/- 3888 vs 789 +/- 718 Pg/ml, P less than 0.01) and epinephrine (298 +/- 229 vs 148 +/- 116 Pg/ml, P less than 0.05) were significantly elevated as well, in contrast to dopamine levels (188 +/- 94 vs 169 +/- 134 Pg/ml N. S.). This finding seems to indicate that dopamine synthesis goes down during hypoxia probably because the rate limiting enzyme in dopamine synthesis, tyrosine, hydroxylase, is inhibited in hypoxia.
mesh_terms: D002395:Catecholamines / Q000097:blood*; D004298:Dopamine / Q000097:blood; D004837:Epinephrine / Q000097:blood; D005260:Female; D005312:Fetal Blood / Q000032:analysis*; D005311:Fetal Hypoxia / Q000097:blood / Q000175:diagnosis*; D006801:Humans; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000097:blood*; D066298:In Vitro Techniques; D007231:Infant, Newborn; D009638:Norepinephrine / Q000097:blood; D011247:Pregnancy; D014471:Umbilical Veins
chemical_list: D002395:Catecholamines; D007042:Hypoxanthines; D019271:Hypoxanthine; D004298:Dopamine; D009638:Norepinephrine; D004837:Epinephrine