Synchronized maternal-infant elevations of primate CSF CRF concentrations in response to variable foraging demand.
BACKGROUND
The study of environment-gene interactions during neurodevelopment may facilitate our understanding of the origins of psychiatric disorders. Environmental contribution to the neurobiology of psychopathology is perhaps most relevant during infancy, where vulnerability to early-life stressors is particularly evident.


OBJECTIVE
In the current study, we wished to examine if central corticotropin-releasing factor (CRF) would provide a plausible biological vehicle for synchronized increases in mothers and their infant.


METHODS
Twenty-four mother-infant bonnet macaques (Macaca radiata) dyads, of known age and weight served as subjects. The subjects were group-housed in four pens of 5-7 dyads each, stabilized for several weeks prior to the study period. Although adequate food was always available, mothers faced uncertainty of food availability for 16 weeks within the first year of infant life, through a procedure dubbed "variable foraging demand" (VFD). Pre- and post-VFD cerebrospinal fluid (CSF) samples were obtained simultaneously on mothers and infants.


RESULTS
Maternal CSF CRF concentrations exhibited a significant mean elevation of 26% from pre-VFD to post-VFD; there was no effect of number of days postpartum on maternal pre-VFD CSF CRF levels. There was a significant mean increase (45%) in infant CSF CRF concentrations over the 16-week period of the VFD paradigm. No infant sex differences were evident. Post-VFD minus pre-VFD differences in infant CSF CRF concentrations were positively correlated (r = .52; N = 16; P = .0384) with the magnitude of maternal CRF response to VFD, providing evidence of synchronized CSF CRF expression by the dyad.


CONCLUSIONS
This parallel response within the dyad suggests, as one testable hypothesis, that maternal responsivity to the stress of the VFD condition is "communicated" between mother and infant via a CRF-mediated mechanism. The VFD stressor produces a parallel activation of the central CRF system in both mothers and their infants.
Coplan
Jeremy D
JD
Department of Psychiatry, State University of New York Downstate Medical Center, Brooklyn, NY 11203, USA. Copstat00@aol.com
Altemus
Margaret
M
Mathew
Sanjay J
SJ
Smith
Eric Lp
EL
Sharf
Bruce
B
Coplan
Paul M
PM
Kral
John G
JG
Gorman
Jack M
JM
Owens
Michael J
MJ
Nemeroff
Charles B
CB
Rosenblum
Leonard A
LA
D000818:Animals; D000831:Animals, Newborn; D001070:Appetitive Behavior / Q000502:physiology*; D001522:Behavior, Animal; D003346:Corticotropin-Releasing Hormone / Q000134:cerebrospinal fluid*; D005247:Feeding Behavior / Q000502:physiology*; D008255:Macaca radiata; D008425:Maternal Behavior
D003346:Corticotropin-Releasing Hormone