The pituitary gland is one of the glands that are involved in the secretion of hormones in the body. The gland is located in the brain and is divided into two, an anterior and a posterior lobe. The hormones secreted by the anterior lobe include thyroid - stimulating hormone (TSH), Follicle-stimulating hormone (FSH), Luteinizing hormone (LH), Prolactin, Adrenocorticotropic hormones (ACTH), Growth hormone(GH), Melanocyte-stimulating hormones(MSH).
Thyroid-stimulating hormone is a hormone, which triggers the thyroid gland to secrete thyroxine, and then triiodothyronine which triggers almost every tissue’s metabolism in the body. It is a glycoprotein hormone that is made and released by thyrotrope cells. Thyroid hormones are involved in the stimulation of varied activities of metabolism that occur in most tissues. The activity of the hormone increases the rate of basal metabolism (Sacher & McPherson, 2000).
Follicle-stimulating hormone is made and released by anterior pituitary gland’s gonadotrophs. It regulates the growth, development, pubertal maturation, as well as reproduction of the body. FSH triggers the growth and immature ovarian follicles recruitment in the ovary. In early antral follicles, FSH is the main factor of survival that saves the small antral follicles. In the luteal-follicle stage change period, the serum degrees of estrogen and progesterone reduce and no longer inhibit the FSH release, therefore, FSH peaks at about third menstrual flow day. The small antral follicles’ cohort is normally adequately in number to make sufficient Inhibin B to reduce serum levels of FSH (Seeley, Stephens, & Tate, 2004).
Luteinizing hormone is a hormone made by gonadotroph cells. In females, an acute LH rise stimulates ovulation and corpus luteum’s development. In males, it triggers Leydig cell testosterone production. The hormone works synergistically with FSH. The luteinizing hormone is also necessary in the maintenance of the luteal function especially for the initial two weeks of the menstrual cycle (Louvet, Harman, & Ross, 1975).
Prolactin refers to a protein coded for by the PRL gene in human and is well known for the role that it plays in lactation. The effects that result from the activity of prolactin are more than 300 and include the stimulation of the mammary glands for the production of milk, mammary glands enlargement in the breast and prepare the breast for the production of milk (Evans, Petersen, Sekhon, & DeMars, 1989).
Adrenocorticotropic hormone (ACTH), also referred to as corticotropin, is a hormone that is polypeptide tropic in nature. The hormone plays a crucial part in the hypothalamic-pituitary-adrenal axis where it is released after the body suffers a biological stress. The principle effects of the hormone include the production as well as in the release of corticosteroids (Seeley, Stephens, & Tate, 2004).
Growth hormones are the peptide hormones involved in the stimulation of processes in human and other animals such as cell reproduction, growth and regeneration. The effects resulting from the growth hormones on the body tissues are generally referred to as anabolic or building up hormone effects.
The melanocyte-stimulating hormones are involved in the stimulation of both the production and the release of the melanin by the melanocytes that are located in the skin and hair. The signals sent by this hormone to the brain have effects sexual arousal and appetite (Seeley, Stephens, & Tate, 2004).
The hormones that are produced by the glands located in the posterior lobe of pituitary glands are antidiuretic hormone (ADH) and the oxytocin. Antidiuretic hormone are also referred to as arginine vasopressin and are involved in the conservation of body water content through the reduction of water loss in urine. On the other hand, oxytocin is involved in neuromodulation activities in the brain (Seeley, Stephens, & Tate, 2004).
Evans, A. M., Petersen, J. W., Sekhon, G. S., & DeMars, R. (1989). Mapping of prolactin and tumor necrosis factor-beta genes on human chromosome 6p using lymphoblastoid cell deletion mutants. Somat. Cell Mol. Genet., 15(3), 203–213.
Louvet, J., Harman, S., & Ross, G. (1975). Effects of human chorionic gonadotropin, human interstitial cell stimulating hormone and human follicle-stimulating hormone on ovarian weights in estrogen-primed hypophysectomized immature female rats. Endocrinology, 96(5), 1179-1186.
Sacher, R., & McPherson, R. A. (2000). Wildmann's Clinical Interpretation of Laboratory Tests (11th ed.). Philadelphia: F.A. Davis Company.
Seeley, R., Stephens, T. D., & Tate, P. (2004). Anatomy and Physiology (6th ed.). New York: The McGraw Hill Companies.