However, the pituitary is really not the master. These releasing factors then cause or inhibit the release of pituitary hormones which travel via the circulatory sytem to the target organ. LH then travels to the ovaries where it causes ovulation and the subsequent development of a progesterone secreting corpus luteum. All except growth hormone and prolactin regulate the activities of other glands. Somatotropin, PRL and ACTH are polypeptide hormones and LH, FSH, and TSH are glycoproteins having very similar structures.
Growth hormone has no specific target tissue.
All cells of the human body are affected by this hormone. It is very important in the growing child but it remains essential to many bodily functions throughout life. GH has effects on the growth of bone and cartilage , protein metabolism, RNA formation , electrolyte balance, fat and glucose metabolism. ACTH This trophic hormone stimulates the production and release of suprarenal steroids. Normally the amount of circulating ACTH is controlled by the levels of cortisol in the blood, individual biorhythms and stress.