Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P01275 (
glucagon
)
26,492
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Secretion of catecholamines may play an important role in several of the adaptations that characterize the transition from intra- to extrauterine life including cardiovascular, respiratory, and metabolic events, specifically the initiation of endogenous glucose production following curtailment of the transplancental maternal supply of glucose. Maturation of neural and enzymatic pathways involved in catecholamine secretion occurs late in gestation;
fetal hypoxia
can produce a 20- and 125-fold increase in plasma epinephrine (E) and norepinephrine (NE), respectively. Estimates of turnover (approximately 2,000 pg X kg-1 X min-1) and metabolic clearance rates (20-40 ml X kg-1 X min-1) indicate active secretion and metabolism of E from fetal sources with negligible transfer from the mother. Simultaneously, there is maturation of functional alpha- and beta-adrenergic receptors. At birth, plasma E and NE rise three- to tenfold; plasma levels are higher in hypoxic infants and lower in prematures. Concurrently,
glucagon
increases three- to fivefold; cortisol and growth hormone also are high, whereas insulin remains low and poorly responsive to stimuli; the number of
glucagon
receptors increases, whereas that of insulin decreases. Acting in concert these hormonal changes activate glycogenolysis, gluconeogenesis, lypolysis, and ketogenesis. Glucose production and gluconeogenesis, absent in utero, become evident within hours of birth in both humans and sheep. The spontaneous surge in catecholamine secretion at birth may be the key event because infusion of E or NE to fetal sheep in late gestation simulates the metabolic and hormonal profile of
glucagon
and insulin as well as glucose production that normally only occur with separation of the placenta.
...
PMID:Fetal-perinatal catecholamine secretion: role in perinatal glucose homeostasis. 633 Nov 91