EXPORT CITATION

Chapter-25 Hormones of Pituitary, Thyroid, Parathyroid, Adrenal Cortex, Ovary and Testes

BOOK TITLE: Drug Screening Methods

Author
1. Halder Nabanita
ISBN
9788180613975
DOI
10.5005/jp/books/10243_25
Edition
1/e
Publishing Year
2004
Pages
41
Author Affiliations
1. All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110 029, (India), All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India, Dr Rajendra Prasad Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India, Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
Chapter keywords
hormonal system, metabolic functions, chemical reactions in the cells, cell membranes, cellular metabolism, cessation of epiphyseal growth, hypophysectomy, prolactin, glycoprotein hormone, adrenocorticotropin hormone (ACTH), hormones, intracellular cAMP, peptides, cell surface receptor, hypophysectomized or dexamethasone blocked rats, corticosterone level, venous blood, oxytocics, uterine contractions, isolated uterus, oxytocin, oxytocic activity, vasopressin, antidiuretic and vasopressor effects, body fluid osmolality, thyroid gland, thyroxine, triiodothyronine

Abstract

The hormonal system is concerned principally with control of the different metabolic functions of the body, such as the rates of chemical reactions in the cells or the transport of substances through cell membranes or other aspects of cellular metabolism like growth and secretion. Cessation of epiphyseal growth occurs after hypophysectomy. Prolactin is a glycoprotein hormone with specific activity. Adrenocorticotropin hormone (ACTH) was one of the first hormones that were shown to cause an increase in intracellular cAMP and one of the first peptides shown to bind specifically and reversibly to a cell surface receptor. In hypophysectomized or dexamethasone blocked rats, ACTH activity can be measured by the increase in corticosterone level in venous blood. Oxytocics are agents that increase the force and frequency of uterine contractions. Isolated uterus of virgin guinea pigs is very sensitive to oxytocin and is used to determine the oxytocic activity of the unknown compounds. Vasopressin has both antidiuretic and vasopressor effects and is the main hormone regulating the body fluid osmolality. Thyroid gland secretes two hormones thyroxine and triiodothyronine, commonly called as T4 and T3. Administration of the exogenous goitrogenic compounds block thyroid hormone secretion resulting in reduced thyroid hormone level in circulation. Parathyroid (PTH) hormone acts chiefly on bone and kidney by regulating calcium and phosphate passage. Cytochemical bioassay method has been developed to determine agonist and antagonist activities of parathyroid hormone analogue. Glucocorticoid induces tyrosine aminotransferase synthesis in hepatoma tissue culture cells. Reduction in eosinophillic cell count occurs in animals as well as in man by glucocorticoids. Liver glycogen test is a simple and specific test for evaluation of glucocorticoid activity. Mineralocorticoids are described. The principal circulating androgen in men is testosterone. Progesterone is produced by corpus luteum and converts the uterine epithelium from proliferative to secretory phase. Progesterone enhances endometrium carbonic anhydrase activity. Estrogens are discussed.

© 2019 Jaypee Brothers Medical Publishers (P) LTD.   |   All Rights Reserved