beta-endorphin and Asphyxia-Neonatorum

Topics: Adaptation, Physiological; Arginine Vasopressin; Asphyxia Neonatorum; beta-Endorphin; Catecholamines; Erythropoietin; Fetal Blood; Humans; Infant, Newborn; Stress, Physiological

Perinatal asphyxia is one of the major causes of cerebral injury in neonates. It may be due to the increased endogenous opioid-like substances (OLS) in the body. The levels of three OLS, namely leucine-enkephalin (LEK), beta-endorphin (beta-EP) and dynorphin A1-13 (DynoA1-13) of 44 cases with neonatal asphyxia were studied by radioimmunoassay. The OLS level in plasma and cerebral spinal fluid (CSF) were higher in asphyxiated group than those in the control group, especially in asphyxiated cases with fetal distress. The OLS levels of CSF were also higher in cases with cerebral injury than in those without cerebral injury, while the levels of OLS in plasma had no difference in these two groups. The relationship between OLS levels and asphyxia and cerebral injury is also discussed.

Topics: Asphyxia Neonatorum; beta-Endorphin; Cerebral Hemorrhage; Dynorphins; Enkephalin, Leucine; Female; Fetal Hypoxia; Humans; Infant, Newborn; Male; Peptide Fragments; Pregnancy

The effects of analgesia on plasma beta-endorphin (beta-E), serum cortisol and blood glucose responses were investigated in 20 distressed, mechanically ventilated neonates during the first 3 days of life. Morphine 0.1 mg/kg, meperidine 1 mg/kg or alfentanil 10 micrograms/kg were used for analgesia as clinically indicated. Plasma beta-E, serum cortisol and blood glucose were recorded before analgesia and 1 and/or 2, 12 and 24 h afterwards in the distress group and once in 20 healthy neonates (control group). beta-E, cortisol, and blood glucose before analgesia were significantly higher in the distress group than in the control group. Cortisol values had decreased significantly 2 h after analgesia and blood glucose within 12 h. Plasma beta-E values had decreased to the same level as in the controls 24 h after the start of analgesia. The results indicate that the stress response in the distressed neonates with cardiorespiratory problems, as assessed by beta-E, cortisol, and blood glucose, is attenuated by opioid medication, and it is concluded that these patients should be given adequate analgesia.

Topics: Analgesia; Apgar Score; Asphyxia Neonatorum; beta-Endorphin; Blood Glucose; Cardiovascular Diseases; Gestational Age; Heart Defects, Congenital; Humans; Hydrocortisone; Infant, Newborn; Persistent Fetal Circulation Syndrome; Respiration Disorders; Respiratory Distress Syndrome, Newborn

In an attempt to prove whether beta-endorphin diurnal rhythm existed in neonates, 17 infants with a mean (+/- SD) gestational age of 31.7 +/- 4.8 weeks and a birth weight of 1,790 +/- 898 g were studied at a mean postnatal age of 3.3 +/- 0.5 days. Plasma samples were obtained from a pre-existing umbilical arterial line at 09.00 h, noon and 15.00 h. Mean plasma concentrations of beta-endorphin were 68.3 +/- 27.7, 54.5 +/- 13.7, and 45.1 +/- 10.8 pg/ml, respectively. Highly significant (p = 0.0002) variation of plasma beta-endorphin concentration was observed in these neonates suggesting the presence of a diurnal rhythm of beta-endorphin in neonates. It is important to specify the time of collection of blood samples for determination of opiates in neonates.

Topics: Asphyxia Neonatorum; beta-Endorphin; Cerebral Hemorrhage; Circadian Rhythm; Humans; Hyaline Membrane Disease; Infant, Newborn; Radioimmunoassay

Twenty-nine premature infants were studied to determine whether neonatal asphyxia, apnea, and low blood pressure in the first day of life are associated with elevated plasma beta-endorphin concentrations. Plasma beta-endorphin levels were determined at 0.5 to 2, 4 to 6, and 18 to 24 hours of life, using radioimmunoassay. Premature infants with moderate or severe asphyxia (n = 19) had higher levels at 0.5 to 2 hours of age (32.1 +/- 6.7 vs 16.4 +/- 7.4 pmol/L) and significantly higher levels at 4 to 6 hours of age (50.4 +/- 10.0 vs 22.9 +/- 9.2 pmol/L) compared with the ten nonasphyxiated premature infants. A significant elevation in levels at age 0.5 to 2 hours (39.4 +/- 9.9 vs 17.7 +/- 4.4 pmol/L) and age 4 to 6 hours (59.3 +/- 13.8 vs 27.1 +/- 17.1 pmol/L) was observed in premature infants with low blood pressure or impaired perfusion (n = 12) who required the administration of volume expanders. No differences were observed in premature infants with and without apnea. It may be speculated that the increased endogenous release of beta-endorphins in response to perinatal asphyxia may play a role in the pathogenesis of shock observed in the first day of life.

Topics: Apnea; Asphyxia Neonatorum; beta-Endorphin; Endorphins; Humans; Hypotension; Infant, Low Birth Weight; Infant, Newborn; Infant, Premature, Diseases; Radioimmunoassay

Topics: Apgar Score; Asphyxia Neonatorum; beta-Endorphin; Endorphins; Humans; Infant, Newborn; Time Factors

beta-Endorphinlike Immunoreactivity (BLI) was measured in sterile, bloodless samples of cerebrospinal fluid (CSF) during the first 24 hours of life in order to assess the relationship between perinatal asphyxia and endogenous opioid activity within the central nervous system. The median CSF BLI in infants with one-minute Apgar scores of 1 to 4 was 148 pg/mL (range, 96 to 171 pg/mL) and that of infants with Apgar scores of 5 to 9 was 78 pg/mL (range, 25 to 162 pg/mL). The linear regression equation correlating CSF BLI with one-minute Apgar score was y = -10.7x + 169.1. Our findings of a highly significant inverse correlation between one-minute Apgar scores and CSF BLI support the hypothesis that perinatal asphyxia is associated with increased activity of opioid systems in the central nervous system.

Topics: Apgar Score; Asphyxia Neonatorum; beta-Endorphin; Endorphins; Female; Gestational Age; Humans; Infant, Newborn; Male; Radioimmunoassay; Regression Analysis; Time Factors

In an attempt to determine whether hypoxic-ischemic encephalopathy in and of itself or its associated pathologic conditions lead to increased concentrations of plasma beta-endorphin (beta-ED), measurements were made in three groups of term infants. Group 1 (control) consisted of 8 infants with a mean gestation of 38.6 +/- (SE) 0.4 weeks, a mean birth weight of 3,420 +/- 150 g, and a mean postnatal age of 1.4 +/- 0.7 days. Group 2 consisted of 10 infants with a mean gestational age, birth weight and postnatal age of 40.1 +/- 0.5 weeks, 3,310 +/- 80 g and 3,9 +/- 1.1 days, and group 3 included 6 infants with a mean gestational age, birth weight and postnatal age of 40.4 +/- 1 weeks, 3,650 +/- 310 g, and 2.8 +/- 1 days, respectively. The group 2 and 3 infants suffered clinical and neurological evidence of hypoxic-ischemic brain injury from perinatal asphyxia; however, the infants in group 2 suffered additional problems such as meconium aspiration, persistent fetal circulation with ongoing hypoxemia as measured by transcutaneous or umbilical arterial oxygen monitoring. The group 3 infants were normoxemic after resuscitation. The mean plasma beta-ED concentrations were 19 +/- (SE) 2.7, 103 +/- 35.7 and 25 +/- 4.5 pg/ml in groups 1, 2 and 3, respectively. A significant elevation of plasma beta-ED concentration was observed in group 2 when compared to groups 1 and 3. The association of increased plasma beta-ED concentration in infants with hypoxic-ischemic encephalopathy associated with ongoing hypoxemia suggests that hypoxemia may act as a strong stimulus for plasma beta-ED release in term infants.

Topics: Asphyxia Neonatorum; beta-Endorphin; Birth Weight; Brain Diseases; Endorphins; Female; Fetal Hypoxia; Gestational Age; Humans; Infant, Newborn; Pregnancy