ELEVATED CIRCULATING CALCITONIN-GENE-RELATED PEPTIDE IN UMBILICAL-CORD AND INFANT BLOOD ASSOCIATED WITH MATERNAL AND NEONATAL SEPSIS AND SHOCK

The role of the sensory neuropeptide calcitonin gene-related peptide ( CORP) was studied in preterm and term neonates with sepsis and shock. CGRP levels in blood were measured by RIA. The identity of immunoreact ive CORP (irCGRP) in adult and infant human blood was confirmed by rev erse phase-HPLC. CORP levels were analyzed in a total of 189 samples ( 95 from cord blood and 94 from neonates). The gestational ages ranged from 24 to 43 wk, and the birth weights ranged from 520 to 4445 g. Cor d samples were collected immediately after delivery and infant blood s amples were collected within 12 h of birth. Samples were coded, and th e data were assigned to groups after determination of CORP levels. The re was a weight- and gestation-dependent increase in irCGRP in the new born population. The direct correlation of circulating CGRP with ascen ding birth weight and gestation may have significance in the developme nt of the fetus. Infants with and without certain complications were g rouped in 500-g intervals. CORP levels in cord blood were significantl y elevated when certain stressful situations existed in the mother. Th ese included culture-positive chorioamnionitis, placental abruption, a nd severe preeclampsia. There was a similar elevation in CGRP in patie nt blood in infants with culture-positive sepsis and/or shock with blo od pressure <2 SD from the mean for corresponding gestation. CORP leve ls did not differ between male and female infants and did not appear t o be influenced by type of delivery (vaginal versus cesarean section). There was no significant difference in CGRP level between cord and pa tient blood in preterm neonates, but at term gestation cord blood leve ls were slightly higher than those in the patient blood. These results suggest that inflammation and hemodynamic imbalance (e.g. shock) are associated with increased in CGRP levels in the circulation in neonate s. Future studies will focus on the biologic effects of elevated CORP during neonatal complications and will examine the utility of CORP mea surement for diagnosis and treatment of disease in preterm infants.