[Abstract Title]. - Society for Neuroscience

Program#/Poster#: 290.13/RR64
Topic: F.02.j. Learning and memory: Pharmacology
Title: Behavioral and neural responses to social isolation rearing in the rat as a function of
prenatal choline supplementation
Authors: R. S. ADAMS, *M. J. GLENN;
Psychology, Colby Col., Waterville, ME
Abstract: Choline is a crucial nutrient that contributes to several biological functions and serves
as a precursor molecule to the neurotransmitter acetylcholine. Choline is integral to the
development and function of the central nervous system, and its availability during the prenatal
period has lasting and protective effects on neural function. Researchers have found that prenatal
choline supplementation in the rat enhances learning and memory processes later in life,
especially those involving spatial memory. Researchers have also demonstrated that choline
protects against a number of physical stressors to the neural environment, such as prenatal
alcohol exposure, induced seizures, and chronic stress-induced exposure to corticosteroids.
Compared to the study of these types of physical stressors, relatively little research has examined
the influence of prenatal choline exposure on psychological stress later in life. To contribute to
this field, the present study examined the effects of prenatal choline supplementation on
behavioral and neural reactions to social isolation rearing, which typically produces a number of
behavioral and cognitive deficits in the rat. Pregnant rats were given either a choline-sufficient
(CON; 1.1 mg/kg choline chloride in AIN76A) or a choline-supplemented (SUP; 5 mg/kg
choline chloride) diet during embryonic days 10-22. On postnatal day (PD) 24, the male
offspring were weaned into standard pair-housing (PH) or social isolation (SI) and remained in
these conditions for the duration of the study. In adulthood (PD 60), behavioral measures of
anxiety, exploration, object and place recognition memory, and spatial reference and working
memory were taken. As our neural measure we assessed levels of adult neurogenesis by
quantifying numbers of doublecortin+ neurons in the dentate gyrus. In analyzing behavioral
measures we found several effects of prenatal choline supplementation. SUP rats demonstrated
superior abilities in object and place recognition memory, and spatial reference and working
memory, but were not less anxious than CON rats. Neural measures also revealed higher levels
of adult neurogenesis in some groups of SUP rats. However, our failure to detect consistent
effects of housing in CON rats prevented us from drawing conclusions about the potential for
prenatal choline supplementation to protect against the psychological stress of social isolation.
Even so, these novel findings suggest that the benefits of prenatal choline supplementation may
be contingent upon experiences such as social rearing, and that choline supplementation may
impact an animal‟s sensitivity to environmental conditions.
Disclosures: R.S. Adams, None; M.J. Glenn , None.
Poster