Effects of age and resistance exercise on skeletal muscle interstitial prostaglandin F2α

Prostaglandin (PG) F2α has been shown to contribute to the anabolic events in skeletal muscle. We measured the skeletal muscle interstitial concentration of PGF2α at rest and following a standard bout of resistance exercise in eight young (27±2 year) and eight old (75±4 year) men. Interstitial PGF2α concentration was determined from microdialysate samples obtained from two microdialysis probes placed in the vastus lateralis. Microdialysates were collected 1 h pre- and 5–6, 8–9, and 24–25 h postexercise. The exercise bout consisted of 4 exercises (3 sets of 8 replications at 80% 1 RM per exercise) emphasizing the quadriceps. Interstitial PGF2α levels were not different (P>0.05) between young and old at rest (1.50±0.35 vs. 1.52±0.30 ng ml−1) or at any time point following the resistance exercise bout. For the young and old combined there was a change (P<0.05) in PGF2α levels at 5–6 h (93%) and 8–9 h (95%), which had returned to preexercise levels by 24–25 h. These results show that PGF2α is increased in skeletal muscle following a standard bout of resistance exercise and aging does not alter interstitial levels of this PG at rest or after exercise. These data, coupled with previous findings, suggest that the anabolic factor PGF2α should be considered when discussing the complex processes that regulate muscle mass in young and old individuals.