Learn More
Twelve substrains of inbred senescence-accelerated mice (SAM) have been developed, among which the SAMP8 and SAMP10 strains show a significant age-related deterioration in learning and memory for passive and active avoidance tasks. These strains have, respectively, a low and high incidence of systemic senile amyloidosis. Although we found no amyloid(More)
Nine normal subjects were asked to make either a brisk isometric pinch of a force transducer held between the forefinger and thumb, or to hold a pinch for approximately 15 s and then release the force suddenly without any overt antagonist contraction. EEG activity was averaged about the onset or offset of EMG activity, and movements were made in the(More)
The senescence-accelerated mouse P10 (SAMP10) is a murine model of accelerated senescence characterized by the deterioration of learning and memory with advancing age. In the present study, we examined the distribution of nerve growth factor (NGF) immunohistochemically in SAMP10 mice and its control strain, SAMR1. In both strains, NGF-like immunoreactivity(More)
This study examined age-dependent deficits in the learning and memory of fear conditioning, using a newly developed senescence-accelerated mouse (SAMP8) model of age-related brain dysfunction and its genetically related inbred strain (SAMR1). The mice were classically conditioned to tone by giving aversive foot shocks in a distinct experimental box(More)
This study examined age-dependent deficits in the learning and memory of inferential tasks, using an established senescence-accelerated mouse model in age-related brain dysfunction (SAMP8) and its genetically related inbred strain (SAMR1). The mice learned two sets of nonspatial odor-odor pairs by association learning successively (i.e., A-->B, X-->Y, then(More)
In a series of inbred Senescence-Accelerated mice (SAM) strains, accelerated-senescence prone SAMP substrains show early onset and rapid advancement of senescence. SAMP8 and SAMP10, in particular, exhibit a significant age-related deterioration in memory and learning for passive and active avoidance tasks with, respectively, a low and high incidence of(More)
We describe a reflex evoked in neck muscles by stimulation of afferent fibres in the trigeminal nerve. The clearest responses were seen in averaged, unrectified, monopolar surface electromyographic (EMG) recordings from active sternocleidomastoid muscles after stimulation of the infraorbital nerve. They consisted of a bilateral positive/negative (p19, n31)(More)
Apolipoprotein B (apoB) mRNA is modified by a post-transcriptional editing reaction (C to U) changing a glutamine (CAA) to a translational stop codon (UAA) and producing apoB-48 mRNA in mammalian liver and intestine. Developmental and age-related changes in apoB mRNA editing were studied using two mouse strains with different aging processes (SAM-R/1 with a(More)
We investigated whether neuronal cell loss occurred as a part of normal aging of the retina in the Senescence-Accelerated Mouse, strains SAMP1 and SAMR1, and in the BALB/c mouse. All three strains showed age-related atrophy of the retina after histologically normal development. Morphometrical study revealed the following facts. The rate of loss of(More)