Maternal care

Sequences of aggressive behavior that are composed of characteristic acts and postures following each other rapidly are disrupted. These disorganizing effects parallel the analysis of amphetamine effects on other intricately patterned behaviors such as feeding, maternal care, play behavior, or reproductive interactions. For example, amphetamine suppresses play... 

Stressful early life events, involving abuse or neglect, can have a life-long influence on the stress response, and lead to elevated levels of allostatic load for the lifespan. Overactivity of the stress hormone axis has been linked to prenatal stress or poor maternal care in rodent models, and this overactivity contributes to increased rates of brain and body aging [39]. 

Hofer, H. and East, M.L. (1993c) The commuting system of Serengeti spotted hyaena how a predator copes with migratory prey. III. Attendance and maternal care. Anim. Behav. 46, 575-589. 

D Amato, F. and Cabib, S. (1987). Chronic exposure to a novel odor increases pups vocalizations, maternal care, and alters dopaminergic functions in developing mice. Behavioral and Neural Biology 48,197-205. 

FIG. 4. Diagram of a circadian system in mammals. The master clock in the SCN entrains all non-SCN clocks in the brain and peripheral organs. Light information enters into the SCN, and non-photic information such as restriction feeding and maternal care enter into the peripheral clocks. Additionally, this scheme proposes the existence of non-photic entrainment from information from non-SCN clocks. 

Meaney MJ (2001) Maternal care, gene expression, and the transmission of individual differences in stress reactivity across generations. Annu Rev Neurosci 24 1161-1192 Medina JF, Christopher RJ, Mauk MD, LeDoux JE (2002) Parallels between cerebellum- and amygdala-dependent conditioning. Nat Rev Neurosci 3 122-131 Milad MR, Quirk GJ (2002) Neurons in medial prefrontal cortex signal memory for fear extinction. Nature 420 70-74... 

Repeat-dose neurotoxicity studies may identify behavioral effects or impaired nerve functions that can interfere with mating or maternal care. Developmental neurotoxicity studies have been conducted for specific pesticide classes, following requirements of US-EPA. If such a study is available it can be examined not only for the study-specific endpoints on the developing brain but also compared to the prenatal toxicity study and the two-generation smdy with respect to general endpoints of pre- and postnatal development, respectively. 

Pregnancy duration prolonged Offspring, high birth weights, increased peri-/postnatal pup mortality due to hypoxia and insufficient maternal care if birth process is prolonged or painftil (dystocia)... 

Caldji, C., Tannenbaum, B., Sharma, S., Francis, D., Plotsky, P.M., and Meaney, M.J. (1998) Maternal care during infancy regulates the development of neural systems mediating the expression of fearfulness in the rat. Proc Natl Acad Sci USA 95 5335-5340. 

Liu, D., Diorio, J., Tannenbaum, B., Caldji, C., Francis, D., Freedman, A., et al. (1997) Maternal care, hippocampal glucocorticoid receptors, and hypothalamic-pituitary-adrenal responses to stress. Science 12277 1659-1662. 

Variations in maternal care may serve as the basis for a nongenomic behavioral transmission of individual differences in stress reactivity across multiple generations. Researchers have found evidence of such transmission in mother-pup contact of rats. Variations in maternal licking/grooming and arched back nursing (LG-ABN) given by the mother to her pups have been associated with the development of individual differ-... 

Francis, D.D., Champagne, F.A., Liu, D., and Meaney, M.J. (1999b) Maternal care, gene expression, and the development of individual differences in stress reactivity. Ann NY Acad Sci 896 66-... 

Francis DD, Meaney MJ. Maternal care and the development of stress responses. Cur Opin Neurobiol 1999 9 128-134. 

Schantz SL, Laughlin NK, Van Valkenberg HC, et al. 1986. Maternal care by rhesus monkeys of infant monkey exposed to either lead or 2,3,7,8-tetrachlorodibenzo-p-dioxin. Neurotoxicol 2 637-650. 

Meaney, M. J. and Szyf, M. (2005). Maternal care as a model for experience-dependent chromatin plasticity Trends Neurosci. 28,456-463. 

Pruessner, J. C., Champagne, E, Meaney, M. J., Dagher, A. 2004, Dopamine release in response to a psychological stress in humans and its relationship to early life maternal care a positron emission tomography study using [llC]raclopride, J.Neurosci., vol. 24, no. 11, pp. 2825-2831. 

Figure 2 Anxiety pathways and their interactions. Two fundamentally different mechanisms involved in anxiety and anxiety-like behavior are proposed. The first mechanism is developmental, and its consequences are manifested later in life. Both genetic and environmental factors linked to anxiety can have a deveiopmental origin, as illustrated by the example of the s allele of the 5-HTT, the deficiency in the SHT receptor, and variability in maternal care. The second possible mechanism is not developmental but based on "acute" or current molecular abnormalities that result in anxiety or anxiety-like behavior. Examples include deficiencies in GABAergic neurotransmission and abnormalities in the central CRH system, which have the direct behavioral output of anxiety. It is also proposed that the developmental mechanisms lead to anxiety by converging on the "acute" mechanisms.

Maternal care and adult life anxiety in rodents... 

Brief handling of rat pups results in a lifelong decrease to behavioral and endocrine effects of stress, whereas animals separated from their mothers/litters for longer periods of time, for example, for several hours, exhibit increased anxiety (167). Later studies determined that the critical effect of short-term handling is the increase in maternal care (licking and grooming) after the return of the pups to the nest (3). 

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