Effects of restraint stress in gestation: implications for rodent developmental toxicology studies.
Restraint has been used as a procedure to study the effects of stress on gestation outcome in rodents. The effects of restraint could potentially be used as a model for the impact of general stress produced by high doses of toxicants and other interventions. In mice, restraint in the peri-implantation period leads to implantation failure, and restraint at appropriate times in organogenesis produces cleft palate, supernumerary ribs, and resorption. In rats, there is some evidence for an association with restraint for implantation failure, but not for the morphological anomalies. Restraint in late gestation alters adult sexual behavior of male rat offspring, but consequences for their fertility are not known. Intrauterine growth retardation is not commonly associated with gestational restraint. In the few studies where they have been directly compared, different restraint procedures produced graded, qualitatively different, or no effects. Adrenocortical hormones have been implicated as mediating the effect of restraint on cleft palate, but not on supernumerary ribs, implantation failure, or sexual differentiation. Given the variety of restraint procedures and the varying species-dependent consequences, it is not possible to infer a generalizable pattern of developmental effects due to gestational stress from the restraint literature. As an alternative approach, contemporary methods in gene expression and developmental biology could profitably be applied to understanding different patterns of stress-mediated effects of toxicant exposures on intrauterine development.
Reproductive and Cancer Hazard Assessment Section, Office of Environmental Health Hazard Assessment, California Environmental Protection Agency, Sacramento, California 95812, USA. mgolub@oehha.ca.gov
Mari S
MS
Golub
Marlissa A
MA
Campbell
Farla L
FL
Kaufman
Poorni
P
Iyer
Ling-Hong
LH
Li
James M
JM
Donald
James E
JE
Morgan
D000014:Abnormalities, Drug-Induced / Q000209:etiology*; D000818:Animals; D005314:Embryonic and Fetal Development / Q000187:drug effects*; D023381:Endpoint Determination; D023421:Models, Animal; D012098:Reproduction / Q000187:drug effects; D012149:Restraint, Physical; D012377:Rodentia / Q000196:embryology; D013312:Stress, Physiological / Q000209:etiology*; D013315:Stress, Psychological / Q000209:etiology