Postnatal Changes In Insulin Binding In Slow And Fast-Twitch Rabbit Skeletal-Muscles

Changes of insulin binding characteristics (number of receptors, Kd) were studied in the semimembranosus proprius (SMP) and psoas major (PM) muscle from birth to adult stage. The Kd was about 0.15 10(-9) M in both muscles and did not change with age. The numbers of receptors were similar in both muscles at birth and changed differently thereafter to reach 1.3 fmoles per mg of muscle in the PM and 5.6 in the SMP muscle.