Muscle mass, structural and functional investigations of senescence-accelerated XXXX P8 (SAMP8).

@entity19 @entity262 @entity6288 @entity346 @entity121
UNASSIGNED: Sarcopenia is an age-related @entity262 with @entity121 and loss in mass. Although the senescence-accelerated @entity19 P8 (SAMP8) was reported valid for muscular ageing research, there was no report on the details such as @entity6288 onset time. Therefore, this study was to investigate the change of muscle mass, structure and functions during the development of @entity6288 . Besides the average life span, muscle mass, structural and functional measurements were also studied. Male SAMP8 animals were examined at month 6, 7, 8, 9, and 10, in which the right gastrocnemius was isolated and tested for ex vivo contractile properties and @entity346 while the contralateral one was harvested for muscle fiber cross-sectional area (FCSA) and typing assessments. Results showed that the peak of muscle mass appeared at month 7 and the onset of contractility decline was observed from month 8. Compared with month 8, most of the functional parameters at month 10 decreased significantly. Structurally, muscle fiber type IIA made up the largest proportion of the gastrocnemius, and the fiber size was found to peak at month 8. Based on the altered muscle mass, structural and functional outcomes, it was concluded that the onset of @entity6288 in SAMP8 animals was at month 8. SAMP8 animals at month 8 should be at pre- @entity6288 stage while month 10 at @entity6288 stage. It is confirmed that SAMP8 @entity19 can be used in @entity6288 research with established time line in this study.
