Effects of perinatal stress and drug abuse on maternal behavior and sensorimotor development of affected progeny.

Methamphetamine (MA) is an addictive psychostimulant with significant potential for abuse. Previous rat studies have demonstrated that MA use during pregnancy impairs maternal behavior and induced delayed development of affected pups. The offspring of drug-addictive mothers were often neglected and exposed to neonatal stressors. The present study therefore examines the effect of perinatal stressors combined with exposure to prenatal MA on the development of pups and maternal behavior. Dams were divided into three groups according to drug treatment during pregnancy: controls (C); saline (SA, s.c., 1 ml/kg); MA (s.c., 5 mg/ml/kg). Litters were divided into four groups according to postnatal stressors: controls (N); maternal separation (S); maternal cold-water stress (W); maternal separation plus cold-water stress (SW). The pup-retrieval test showed differences among postnatally stressed mothers and non-stressed controls. The righting reflex on a surface revealed delayed development of pups prenatally exposed to MA/SA and postnatal stress. Negative geotaxis and Rotarod results confirmed that the MA group was the most affected. Overall, our data suggests that a combination of perinatal stress and prenatal MA can have a detrimental effect on maternal behavior as well as on the sensorimotor development of pups. However, MA exposure during pregnancy seems to be the decisive factor for impairment.

Rodent Gymnastics: Neurobehavioral Assays in Ischemic Stroke.

Despite years of research, most preclinical trials on ischemic stroke have remained unsuccessful owing to poor methodological and statistical standards leading to "translational roadblocks." Various behavioral tests have been established to evaluate traits such as sensorimotor function, cognitive and social interactions, and anxiety-like and depression-like behavior. A test's validity is of cardinal importance as it influences the chance of a successful translation of preclinical results to clinical settings. The mission of choosing a behavioral test for a particular project is, therefore, imperative and the present review aims to provide a structured way to evaluate rodent behavioral tests with implications in ischemic stroke.

Performance of Male and Female C57BL/6J Mice on Motor and Cognitive Tasks Commonly Used in Pre-Clinical Traumatic Brain Injury Research.

To date, clinical trials have failed to find an effective therapy for victims of traumatic brain injury (TBI) who live with motor, cognitive, and psychiatric complaints. Pre-clinical investigators are now encouraged to include male and female subjects in all translational research, which is of particular interest in the field of neurotrauma given that circulating female hormones (progesterone and estrogen) have been demonstrated to exert neuroprotective effects. To determine whether behavior of male and female C57BL6/J mice is differentially impaired by TBI, male and cycling female mice were injured by controlled cortical impact and tested for several weeks with functional assessments commonly employed in pre-clinical research. We found that cognitive and motor impairments post-TBI, as measured by the Morris water maze (MWM) and rotarod, respectively, were largely equivalent in male and female animals. However, spatial working memory, assessed by the y-maze, was poorer in female mice. Female mice were generally more active, as evidenced by greater distance traveled in the first exposure to the open field, greater distance in the y-maze, and faster swimming speeds in the MWM. Statistical analysis showed that variability in all behavioral data was no greater in cycling female mice than it was in male mice. These data all suggest that with careful selection of tests, procedures, and measurements, both sexes can be included in translational TBI research without concern for effect of hormones on functional impairments or behavioral variability.