Developmental changes in insulin-like growth factor-I (IGF-I) receptor levels and plasma IGF-I concentrations in large white and Meishan pigs.

摘要: Abstract The developmental pattern of insulin-like growth factor-I receptor (IGF-IR) and plasma IGF-I concentrations were examined in longissimus dorsi (LD), trapezius (TR), liver from the last third gestation up to 1 year age male Large White (LW) Meishan (MS) pigs. Plasma increased between 75 days 180 with a 100-fold increase decreased thereafter. At 365 age, higher LW than MS 125 I-IGF-I specific binding was detected skeletal muscle (not determined fetal TR) until adult stage both breeds. Affinity cross-linking experiments followed by electrophoresis under reducing conditions revealed presence one band an apparent molecular weight 140 kDa LD. In displacement experiments, data indicated that bound specifically IGF-IR prenatal postnatal tissues. Specific 90 It remained elevated 103–113 tended be liver. After birth, it remain stable is concluded similar few differences observed pigs cannot account for their different performances. high fetus suggests may play important role development.