L-Type Voltage-Dependent Calcium Channel Blocker Nifedipine Enhances Memory Retention When Infused into the Hippocampus

Wistar rats with cannulae bilaterally implanted in the CA1 region of the dorsal hippocampus were trained in a step-down inhibitory avoidance task. Through these cannulae they received an infusion of 28 or 280 ng per side of the L-type voltage-dependent calcium channel antagonist nifedipine, or of its vehicle (20% dimethyl sulfoxide in saline). The two doses of the drug were studied by administration 0 or 30 min after training; in addition, the higher dose was studied by infusion 10 min before training. A retention test was carried out 24 h after the training session. The highest dose of nifedipine administered 0 min post-training enhanced test session performance of the animals compared to the control group; the effect of the lower dose was not statistically significant. There was no effect of the drug given 30 min post-training or 10 min pretraining. Despite the inability to discriminate direct neural from indirect vascular effects, these results are consistent with previous reports on nootropic actions of the dihydropyridine class of calcium channel blockers. The data are at variance with the amnestic effect of intrahippocampal nifedipine described by Lee and Lin (1991,Life Sciences,48,1333–1340), which may be attibuted to the different range of doses studied here. This might resemble the inverted U-shaped dose–response curve observed with another dihydropyridine, nimodipine, by other authors.     

Psychometric Properties of the Objectified Body Consciousness Scale (OBCS) in Spanish Preadolescents

Sex Roles - Objectification theory postulates that the body is constructed as a sexual object and is subject to observation and evaluation in such a way that a person may feel that their body is an...     

Air pollution, cognitive deficits and brain abnormalities: a pilot study with children and dogs

Exposure to air pollution is associated with neuroinflammation in healthy children and dogs in Mexico City. Comparative studies were carried out in healthy children and young dogs similarly exposed to ambient pollution in Mexico City. Children from Mexico City (n: 55) and a low polluted city (n:18) underwent psychometric testing and brain magnetic resonance imaging MRI. Seven healthy young dogs with similar exposure to Mexico City air pollution had brain MRI, measurement of mRNA abundance of two inflammatory genes cyclooxygenase-2, and interleukin 1 beta in target brain areas, and histopathological evaluation of brain tissue. Children with no known risk factors for neurological or cognitive disorders residing in a polluted urban environment exhibited significant deficits in a combination of fluid and crystallized cognition tasks. Fifty-six percent of Mexico City children tested showed prefrontal white matter hyperintense lesions and similar lesions were observed in dogs (57%). Exposed dogs had frontal lesions with vascular subcortical pathology associated with neuroinflammation, enlarged Virchow-Robin spaces, gliosis, and ultrafine particulate matter deposition. Based on the MRI findings, the prefrontal cortex was a target anatomical region in Mexico City children and its damage could have contributed to their cognitive dysfunction. The present work presents a groundbreaking, interdisciplinary methodology for addressing relationships between environmental pollution, structural brain alterations by MRI, and cognitive deficits/delays in healthy children.