Mother‐infant interaction and the modulation of pituitary‐adrenal activity in rat pups after early stimulation

Smotherman, William P.

doi:10.1002/dev.420160303

Cited by 61 publications

(53 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Given that all rats underwent identical TBI, with strict temperature control during the peri-injury and recovery periods, it is unclear why a subset of rats displayed a different response to injury. Maternal rearing characteristics are influential to rat pup development and may alter response to stress in immature rats (Pryce and Feldon, 2003;Smotherman, 1983). Although maternal rearing may have contributed to injury response in our study, those rats showing post-injury hypertrophy were not reared in a single litter.…”

Section: Discussionmentioning

confidence: 85%

Traumatic brain injury during development reduces minimal clonic seizure thresholds at maturity

et al. 2008

View full text Add to dashboard Cite

Post-traumatic seizures affect 12 -35% of children after traumatic brain injury (TBI) and are associated with worse cognitive and functional outcome, even after adjustment for severity of injury. Unfortunately, experimental models of pediatric post-traumatic epilepsy are lacking, and pathogenesis remains poorly understood. We have applied a standard model of TBI in immature rats to determine the effect of TBI on electroconvulsive seizure thresholds later in life.Male rats underwent controlled cortical impact to left parietal cortex on post-natal day (PND) 16-18. Hindbrain, forebrain, and limbic seizure thresholds were assessed, respectively, by tonic hindlimb extension (THE), minimal clonic, and partial psychomotor seizure responses during adolescence and at maturity (PND 60 -63). Post-traumatic seizure thresholds were compared to those obtained in age-and litter-matched sham craniotomy and naïve controls.TBI during immaturity had no clear effect on THE seizure thresholds. In contrast, TBI lowered minimal clonic seizure thresholds at maturity (p < 0.05 vs. sham or naïve rats), but not during adolescence. Consequently, minimal clonic seizure thresholds increased with age for sham and naïve rats but remained similar for TBI rats during adolescence and at maturity. TBI also tended to lower partial psychomotor seizure thresholds, which were determined only during adolescence (p < 0.1 vs. naive).Controlled cortical impact causes both focal cortical injury at the site of impact and ipsilateral hippocampal neuronal death. Since minimal clonic seizures are mediated by the forebrain, partial psychomotor seizures by the limbic system, and THE seizures by the brainstem, the observed pattern of changes in post-traumatic seizure thresholds is not surprising. The apparent age-dependent effects of TBI, however, are unexpected and likely due to a combination of attenuated maturational increases

show abstract

Section: Discussionmentioning

confidence: 85%

Traumatic brain injury during development reduces minimal clonic seizure thresholds at maturity

et al. 2008

View full text Add to dashboard Cite

show abstract

“…When taken to the extreme, this view would directly contradict the stress-activation hypothesis (10,11), which states that the nonmaternal environment has a direct effect on the offspring by activating some aspects of the offspring's hypothalamic-pituitary-adrenal (HPA) function. In contrast, the "maternal modulation view" incorporates the stressactivation hypothesis and assumes that the nonmaternal environment first activates aspects of the HPA axis, and the mother then modulates this effect (12). According to the latter view, the individual mother sets distinct contexts for the same nonmaternal environment to result in different developmental outcomes.…”

mentioning

confidence: 99%

Maternal modulation of novelty effects on physical development

Tang

Yang²,

Reeb‐Sutherland³

et al. 2012

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Familiarity to the mother and the novelty afforded by the postnatal environment are two contrasting sources of neonatal influence. One hypothesis regarding their relationship is the maternal modulation hypothesis, which predicts that the same neonatal stimulation may have different effects depending on the maternal context. Here we tested this hypothesis using physical development, indexed by body weight, as an endpoint and found that, among offspring of mothers with a high initial swim-stress-induced corticosterone (CORT) response, neonatal novelty exposure induced an enhancement in early growth, and among offspring with mothers of a low initial CORT response, the same neonatal stimulation induced an impairment. At an older age, a novelty-induced increase in body weight was also found among offspring of mothers with high postnatal care reliability and a novelty-induced reduction found among offspring of mothers with low care reliability. These results support a maternal modulation of early stimulation effects on physical development and demonstrate that the maternal influence originates from multiple instead of any singular sources. These results (i) significantly extend the findings of maternal modulation from the domain of cognitive development to the domain of physical development; (ii) offer a unifying explanation for a previously inconsistent literature regarding early stimulation effects on body weight; and (iii) highlight the notion that the early experience effect involves no causal primacy but higher order interactions among the initial triggering events and subsequent events involving a multitude of maternal and nonmaternal influences.maternal stress | maternal care | maternal mediation | developmental plasticity | growth enhancement I t seems self-evident that, for a developing infant, both the maternal and nonmaternal environment affects his or her development. Over the past century, ample evidence from both human and animal early-experience studies has confirmed this intuition (1-3). What remains challenging is how these two environmental sources interact to jointly influence offspring development (4-7). Emerging from the rodent developmental literature are two alternative views regarding the relation between maternal and nonmaternal influences. The "maternal mediation view" assumes that nonmaternal environment exerts its effect indirectly through its effect on the mother, who in turn affects the offspring (e.g., see refs. 8 and 9). When taken to the extreme, this view would directly contradict the stress-activation hypothesis (10, 11), which states that the nonmaternal environment has a direct effect on the offspring by activating some aspects of the offspring's hypothalamic-pituitary-adrenal (HPA) function. In contrast, the "maternal modulation view" incorporates the stressactivation hypothesis and assumes that the nonmaternal environment first activates aspects of the HPA axis, and the mother then modulates this effect (12). According to the latter view, the individual mother sets distinct conte...

show abstract

“…Specific behaviors of the dam regulate the functioning of many specific behavioral and physiological systems in pups. For instance, periodic milk delivery modulates the sleep-wake cycle of pups (Hofer & Shair, 1982), tactile stimulation, similar to that used in the present study, maintains normal ornithine decarboxylase levels (Butler et al, 1968;Evoniuk et al, 1979;Kuhn et al, 1978), and some unknown nonnutritive aspect of contact with the dam maintains adrenocortical activity at normal levels (Smotherman, 1983;Stanton & Levine, 1984). The results of the present paper indicate that some nonspecific aspect of maternal physical stimulation may also serve to-regulate the body and brain temperature of neonatal pups.…”

Section: Discussionmentioning

confidence: 56%

Physical stimulation reduces the brain temperature of infant rats

Sullivan

Wilson

Leon

1988

Developmental Psychobiology

View full text Add to dashboard Cite

Previous work indicated that physical stimulation, such as that which mimics the stimulation pups receive from the dam, reduces pup body temperature. The present paper reports that the body and brain temperature of 5-day-old pups covaried under steady-state thermal conditions, cold exposure, and warmth exposure (Expt. 1) suggesting that body thermoregulatory mechanisms may also regulate brain temperature. Indeed, physically stimulating pups decreased brain temperature in the neocortex (Expt. 2) and the olfactory bulb (Expt. 3). The mechanism for this brain temperature decrease appears to be an increase in ventilatory heat exchange, the same mechanism responsible for the decrease in body temperature. Pups increased respiration during stimulation, thereby increasing air flow to the lungs where convective and evaporative heat exchange occurred. Indeed, stimulating pups in a highhumidity environment blocked the decrease in brain temperature (Expt. 4). The ability of physical stimulation to decrease brain temperature appears to be limited to neonatal pups, as 10-, 15-, and 20-day-old pups did not exhibit a brain temperature decrease in response to stimulation (Expt. 5).

show abstract

Mother‐infant interaction and the modulation of pituitary‐adrenal activity in rat pups after early stimulation

Cited by 61 publications

References 23 publications

Traumatic brain injury during development reduces minimal clonic seizure thresholds at maturity

Traumatic brain injury during development reduces minimal clonic seizure thresholds at maturity

Maternal modulation of novelty effects on physical development

Physical stimulation reduces the brain temperature of infant rats

Contact Info

Product

Resources

About