Figure 1.

Catecholamine response to delivery of term lambs, preterm lambs and term lambs following adrenalectomy. Fetal term (145±2 day gestation) and preterm (130±1 day gestation) lambs were delivered at 0 time following fetal catheter placement. The adrenalectomy lambs had adrenal glands removed at 138±1 days and received continuous cortisol supplemental until delivery at 142 days gestation. Epinephrine and norepinephrine values are expressed relative to the values measured 10 min prior to delivery. A. Epinephrine increased about 12 fold over the -10 min value for the term lambs, and this increase was ablated by adrenalectomy. The increase in epinephrine was much larger for the preterm lambs. B. There was a similar pattern for the norepinephrine responses. C. Blood pressure increased in term and preterm animals but not in term adrenalectomized animals. D, E. Glucose and free fatty acids in blood increased more for term than preterm lambs with minimal increases following adrenalectomy. Data from Padbury et al (6, 8).