Neuropeptide Y administered into cerebral ventricles stimulates sucrose ingestion in the near-term ovine fetus.
OBJECTIVE
In adults, nutrient intake is controlled by opposing actions of appetite stimulants (eg, neuropeptide Y [NPY]) and suppressors (eg, leptin). Because NPY may exert a preferential role in mediating adult carbohydrate intake, we sought to determine the effect of central NPY on near-term fetal carbohydrate ingestion.


METHODS
Five pregnant ewes and fetuses were prepared with fetal vascular, sublingual, and intracerebroventricular catheters, electrocorticogram, and esophageal electromyogram electrodes and studied at 131+/-2 days' gestation. After a 2-hour baseline period, 10% sucrose was infused sublingually for the duration of the study. At 4 hours' time, NPY was injected into the fetal cerebral ventricles and fetal swallowing monitored for an additional 6 hours.


RESULTS
During the basal period, mean (+/-SEM) swallowing averaged 0.8+/-0.1 swallows per minute. Fetal swallowing increased significantly in response to sublingual sucrose (1.3+/-0.1 swallows/min, P=.001), and further significantly increased at 4 to 6 hours after NPY injection into the cerebral ventricles (1.8+/-0.3, P=.001).


CONCLUSIONS
These results indicate central NPY stimulation of fetal ingestion beyond that resulting from sublingual 10% sucrose. The in utero development of NPY-induced ingestive behavior may be in preparation for high neonatal caloric intake.
El-Haddad
Mostafa A
MA
Perinatal Research Laboratories, Harbor/UCLA Medical Center, University of California, Los Angeles School of Medicine, Torrance 90502, USA. melhaddad@gcrc.rei.edu
Ismail
Yaser
Y
Guerra
Catalina
C
Day
Linda
L
Ross
Michael G
MG
D000818:Animals; D002552:Cerebral Ventricles / Q000187:drug effects*; D005260:Female; D005333:Fetus / Q000502:physiology*; D007276:Injections, Intraventricular; D009478:Neuropeptide Y / Q000008:administration & dosage*; D011247:Pregnancy; D034561:Sheep, Domestic; D013268:Stimulation, Chemical; D013395:Sucrose
D009478:Neuropeptide Y; D013395:Sucrose