Relationship between fetal distress and endogenous opioid peptides levels of the venous blood and the umbilical blood in pregnant women

Dian HU; Hang GU; Xinru HONG; Ningxia SUN; Chenghai WANG

ABSTRACT

BACKGROUND:

Endogenous opioid peptide is an important medium and regulator that participate in many physical and pathologic processes of the body. Its relationship with fetal encephalopathy has attracted much attraction.

OBJECTIVE:

To evaluate the role of endogenous opioid peptides (EOP) in fetal distress.

DESIGN:

A case-control observatory study based on healthy pregnant women.

SETTING:

Wards of the Department of Obstetrics and Gynecology of Changzheng Hospital Affiliated to Second Military Medical University of Chinese PLA.

PARTICIPANTS:

Eighty-three healthy women who were hospitalised in Changzheng Hospital and Changhai Hospital affiliated to the Second Military Medical University of Chinese PLA and met the inclusion criteria. Among them, 40 were normal healthy pregnant women(the control group) and 43 were healthy pregnant women with fetal distress(the fetal distress group).

METHODS:

Radioimmunoassay was used to measure the levels of blood EOP(β-endorphin, dynorphin A1- 13 and leu-enkephalin) of the venous blood of the pregnant women in fetal distress group and the control group and the EOP level in the umbilical blood of the newborns. Also, blood gas analysis of the blood from the umbilical artery was conducted.MAIN OUTCOME

MEASURES:

The levels of EOP in the venous blood of two groups of pregnant women and the umbilical blood of newborns and the correlation of EOP level with fetal distress.

RESULTS:

The levels of the umbilical artery blood EOP(β-endorphin,dynorphin A1-13 and leu-enkephalin) in the fetal distress group[(453± 68 ) ng/L, (242 ± 33)ng/L, and(498 ± 68)ng/L respectively] were significantly higher than those in the control group[ (251 ± 39) ng/L, (103± 22 )ng / L and(322 ± 40 )ng / L respectively ( t = 2. 713,2. 762, P＜ 0.01; t = 2. 132, P ＜ 0.05 ) ]. The umbilical artery blood gas analysis;pH was (7.0 ± 0. 1 ) , PO2 was ( 1.7 ± 0.6) kPa, PCO2 was (8.9 ± 0. 7) kPa.The levels of β-endorphin were negatively correlated with pH and PO2 of the umbilical artery blood(r= -0.418 and -0.437, P ＜ 0.01), but they were positively correlated with PCO2( r = 0. 442, P ＜ 0. 05) . The level of dynorphin A1-13 was negatively correlated with pH and PO2( r = -0. 337,-0.383, P ＜ 0.05), but it was positively correlated with PCO2(r= 0. 346, P ＜ 0. 05). There was no significant difference among the three kinds of blood EOP of the two groups( P ＞ 0.05).

CONCLUSION:

EOP participates in the pathological progress of the fetal distress and was closely correlated with the occurrence and development of the fetal distress. This finding has a reference value for early rehabilitation and intervention after the fetal was born that can be tested quantitatively.