Ovine chorionic somatomammotropin and foetal growth

Area of Science:

• Endocrinology
• Reproductive Biology
• Developmental Biology

Background:

• Ovine chorionic somatomammotropin (oCS) is a bifunctional hormone with both lactogenic and somatotropic activities.
• Serum levels of oCS and ovine growth hormone (oGH) correlate with ovine fetal weight gain.
• oCS stimulates somatomedin production by the fetal liver and has specific receptors in fetal tissues.

Purpose of the Study:

• To investigate the role of ovine chorionic somatomammotropin (oCS) in fetal growth.
• To explore the structure-function relationships between growth hormones and placental hormones.
• To identify somatotropic sites involved in fetal growth.

Main Methods:

• Examined the effects of oCS on weight and bone growth in hypophysectomized rats.
• Analyzed the binding properties of oCS to lactogenic and somatotropic receptors.
• Studied the relationship between oCS and oGH serum levels and fetal weight gain.
• Investigated oCS-stimulated somatomedin production in fetal liver.
• Assessed the presence of oCS receptors in fetal tissues.

Main Results:

• oCS administration enhanced weight and bone growth in hypophysectomized rats.
• oCS demonstrated bifunctional activity, binding to both lactogenic and somatotropic receptors.
• Elevated oCS and oGH serum levels were associated with increased ovine fetal weight.
• oCS was shown to stimulate somatomedin production by the fetal liver.
• Specific oCS receptors were identified in various fetal tissues, implicating oCS in fetal development.

Conclusions:

• oCS plays a significant role in promoting fetal growth.
• oCS functions as a key mediator of fetal growth, distinct from pituitary growth hormone's role in postnatal growth.
• Further research into structure-function relationships can elucidate the specific somatotropic actions of placental hormones.