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Pituitary adenylate cyclase-activating polypeptide (PACAP) in fetal cord blood
Stephen J Winters1, Jeffrey C King2, Carol K Brees2
1Department of Medicine, University of Louisville, United States.
Insights
This study found no significant impact of labor stress on fetal pituitary adenylate cyclase-activating peptide (PACAP) levels in cord blood. Further research is needed to clarify PACAP's role in pregnancy and childbirth.
Area of Science:
- Neuroendocrinology
- Reproductive Biology
- Perinatal Medicine
Background:
- Pituitary adenylate cyclase-activating peptide (PACAP) is a peptide found in the brain, nervous system, and placenta.
- PACAP influences the 'fight-or-flight' response, affecting cortisol and catecholamine production.
- Its role in fetal development and response to labor stress is not fully understood.
Purpose of the Study:
- To investigate the effect of labor as a stressor on fetal PACAP levels.
- To test the hypothesis that PACAP levels increase with labor, abnormal fetal heart tracing, or fetal growth impairment.
Main Methods:
- Collected fetal cord venous blood samples immediately after vaginal or Cesarean delivery.
- Stored samples at -80°C for PACAP immunoassay.
- Analyzed delivery data, including birth weight and Apgar scores.
Main Results:
- Fetal cord blood PACAP levels were similar between males and females.
- A trend suggested higher PACAP levels in neonates delivered via Cesarean section compared to vaginal delivery.
- PACAP levels did not correlate with birth weight, Apgar scores, or the presence of labor.
Conclusions:
- Labor stress did not appear to affect fetal PACAP levels in this study.
- PACAP and its receptors are present in the placenta, and PACAP is found in cord blood.
- More research is required to elucidate PACAP's function during gestation and parturition.
Background:
Pituitary adenylate cyclase-activating peptide (PACAP) is a centrally-acting peptide with highest concentration within the limbic area of the brain. PACAP is also expressed in and affects the functions of vascular and nervous tissues, endocrine glands, and the placenta. PACAP appears to be associated with the 'fight-or-flight' response to emergency partly through its effect on adrenal production of cortisol and catecholamines.
Objectives:
We sought to explore the impact of labor as a stressor on the level of PACAP in the fetus, and hypothesized that PACAP levels would be increased when labor, abnormal fetal heart tracing, or fetal growth impairment was evident.
Methods:
Fetal cord venous blood samples were collected immediately after delivery from a random group of women undergoing either vaginal or Cesarean delivery. The blood was placed in chilled EDTA-aprotinin containing tubes, centrifuged, and stored at -80°C for PACAP immunoassay. Delivery data were abstracted for analysis.
Results:
The level of PACAP in cord blood was similar in both males and females. There was a trend toward higher levels in the cord blood of fetuses delivered by Cesarean compared to those delivered vaginally. PACAP levels were unrelated to birth weight, Apgar scores, and the presence or absence of labor prior to delivery.
Conclusions:
While PACAP and its receptor are expressed in placenta, and PACAP protein is found in cord blood, no effect of labor stress on PACAP was found. Further research is needed to understand the role of PACAP in gestation and parturition.
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