Influence of nutritional status on growth hormone-dependent circulating somatomedin-C activity in mature sheep

J Endocrinol. 1991 Aug;130(2):313-20. doi: 10.1677/joe.0.1300313.


The effect of daily administration of ovine GH for a period of 4 weeks on somatomedin-C biological activity in plasma was investigated in mature Merino sheep fed a maintenance energy intake (low plane; LP) or 1.6 times this amount (high plane; HP). The GH treatment resulted in a significant (P less than 0.05) increase in plasma GH levels in blood samples collected 23.5 h after each daily injection in both LP and HP groups. Plasma concentrations of somatomedin-C activity and insulin were significantly stimulated to a maximum level by the third GH injection and remained at this level for 7 days. Subsequently, circulating levels of both hormones fell to 40-50% of the peak response to GH and returned to basal levels within 48 h of the cessation of GH injections. In the HP group the response of plasma insulin and somatomedin-C activity to GH injection was greater than in the LP group.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Energy Intake / physiology*
  • Female
  • Growth Hormone / pharmacology
  • Growth Hormone / physiology*
  • Insulin / blood
  • Insulin-Like Growth Factor I / metabolism*
  • Nutritional Status / physiology*
  • Sheep / blood
  • Sheep / physiology*
  • Stimulation, Chemical


  • Insulin
  • Insulin-Like Growth Factor I
  • Growth Hormone