Perinatal lead exposure alters locomotion induced by amphetamine analogs in rats.

Aims: The precise neurochemical perturbations through which perinatal (gestation/lactation) lead exposure modifies the reinforcement efficacy of various psychoactive drugs (e.g., cocaine, opiates) are unknown.

Intracranial magnetic resonance imaging artifacts and pseudolesions in dogs and cats.

Normal anatomic variation, study design, external factors, and tissue characteristics can all influence the manifestation of structures on magnetic resonance images (MRI). For the purpose of this review, imaging artifacts are considered to be nonpathologic abnormalities resulting from study design, intrinsic tissue characteristics, or external factors, while MRI pseudolesions are due to normal anatomic variation. Awareness of imaging artifacts and pseudolesions, as well as normal anatomic structures, is important when determining pathologic vs.

Imaging diagnosis--magnetic resonance imaging pseudolesion associated with the petrous temporal bone.

Normal anatomic variation in the amount of fat within the petrous temporal bone of dogs can result in a magnetic resonance (MR) imaging pseudolesion. Focal hyperintense areas in the region of the hippocampus on T1-weighted, T1-weighted, and fluid-attenuated inversion recovery imaging sequences were noted in a dog being imaged for seizure activity. Further investigation of this region, aided by the use of cadaveric specimens, led to the identification of normal anatomic variability in the amount of fat in the substantia spongiosa of the petrous temporal bone.

Prenatal lead exposure enhances methamphetamine sensitization in rats.

Adult female rats were exposed to lead-free sodium acetate via gavage [0 mg (vehicle control)] or to 16 mg lead as lead acetate for 30 days prior to breeding. Following confirmation of breeding, the female animals continued to be exposed to their respective doses throughout gestation and lactation. When weaned, 16 control and 16 lead-exposed offspring were placed on regular water and food (lead-exposure was discontinued) until postnatal day (PND) 70.