Related Experiment Videos
Fetal intermediate lobe is stimulated by parturition
F Facchinetti1, A Lanzani, A R Genazzani
1Department of Obstetrics and Gynecology, School of Medicine, University of Modena, Italy.
American Journal of Obstetrics and Gynecology
|November 1, 1989
Summary
Labor stress increases fetal beta-endorphin and desacetylated alpha-melanocyte-stimulating hormone release from the pituitary gland. This study shows parturition activates proopiomelanocortin peptide release, with the fetus secreting active beta-endorphin.
Area of Science:
- Endocrinology
- Neuroscience
- Reproductive Biology
Background:
- The fetal pituitary gland's response to labor stress is not fully understood.
- Different forms of endorphins, including N-acetyl-beta-endorphin and desacetylated alpha-melanocyte-stimulating hormone, are found in the fetal pituitary.
- These peptides originate from the pituitary intermediate lobe, which may be sensitive to labor stress.
Purpose of the Study:
- To assess the sensitivity of the fetal pituitary intermediate lobe to labor stress.
- To evaluate the levels of beta-endorphin, N-acetyl-beta-endorphin, melanocyte-stimulating hormone, and desacetylated alpha-melanocyte-stimulating hormone in maternal and cord blood during vaginal delivery versus elective cesarean section.
- To determine if parturition influences the release of proopiomelanocortin (POMC) peptides.
Main Methods:
- Plasma peptide levels were measured using specific radioimmunoassays.
- Peptides were extracted using Sep-Pak C-18 cartridges and fractionated by high-performance liquid chromatography (HPLC).
- Samples were collected from mothers and newborns during vaginal deliveries and elective cesarean sections.
Main Results:
- Cord blood levels of beta-endorphin and desacetylated alpha-melanocyte-stimulating hormone were significantly higher in vaginally delivered infants compared to those delivered by cesarean section.
- Maternal plasma beta-endorphin levels were also higher in women who delivered vaginally.
- N-acetyl-beta-endorphin and alpha-melanocyte-stimulating hormone levels did not differ based on the mode of delivery. Fetal and maternal peptide levels were similar in cesarean section cases.
Conclusions:
- Parturition activates proopiomelanocortin peptide release from both the anterior and intermediate pituitary lobes.
- The fetus secretes active beta-endorphin, capable of binding to opiate receptors, in response to labor.
- Desacetylated alpha-melanocyte-stimulating hormone may be co-secreted with beta-endorphin, potentially linked to adrenal androgen activation at birth.