| Endocrine Disruption |
Glossary
Activational Effect 1) acute effect of hormone. 2) typically post-development (as opposed to organizational effect). Adenohypophysis anterior lobe of the pituitary gland. synthesizes and releases hormones in response to hypothalamic signaling. Adrenergic pertaining or relating to catecholamines (i.e., epinephrine, norepinephrine, or dopamine). Anti-Androgen chemical that acts as an antagonist at the androgen receptor or otherwise interferes with the effects of endogenous androgens. Aromatase enzyme (e.g., CYP19) that converts testosterone to estradiol. Aromatization process by which a compound forms aromatic ring (e.g., T to E2). Beta-Endorphin one of several peptides, secreted in the brain, which has pain-relieving effects similar to morphine. Critical Period the limited time frame in which an important development or action must occur (e.g., sexual differentiation). Cryptorchidism condition in which the testes do not descend into the scrotum. Cyclopentenoperhydrophenanthrene Nucleus a backbone structure common to cholesterol and its derivatives (e.g., steroid hormones). back to top Defeminization loss of female secondary sex characteristics. Double-Blind 1) a kind of clinical study in which neither the participants nor the person administering treatment know which treatment any particular subject is receiving. 2) a method to reduce experimental bias. Endocrine Disruption process by which an exogenous substance causes adverse health effects consequent to changes in endocrine function. Endogenous synthesized inside the body. Environmental Signaling 1) intracellular effects of exogenous chemical stimuli that mimic or antagonize effects of endogenous hormones. 2) effect of any stimulus originating from outside the body. Estrogen 1) a class of steroid hormones, secreted primarily from the ovaries, that is responsible for initiation of estrus and for the development of secondary sexual characteristics in the female (e.g., 17ß-estradiol). 2) a chemical that mimics the effects of endogenous estrogen (e.g., an environmental estrogen). Estrogen Receptor Beta estrogen receptor that is the product of a separate gene from ER-alpha and distributed throughout the body with highest expression in prostate and ovaries. Exogenous made outside the body. Gamete/Germ Cell cell produced by gonad that contains half of genes necessary for production of offspring (e.g., oocyte in female, spermatozoan in male). Gene basic unit of heredity. occupies a specific place on a chromosome. Glycosylation the process of adding sugar groups to a molecule. Gonad an organ that produces cells (oocytes, spermatozoa) and hormones (estrogen, progesterone, testosterone) necessary for reproduction ( e.g., ovary [female] or testis [male]). Gonadotropin 1) hormone (released from pituitary gland) that stimulates the gonads. 2) word comes from gonad, tropic (moves toward). back to top Heterodimer a structure consisting of unlike subunits. Homodimer structure in which 2 identical subunits are associated. Hormone traditionally, a chemical substance produced by one part of the body that has an effect on another part of the body. Hormone Replacement Therapy (HRT) the administration of estrogen and progestin to women to relieve the symptoms of menopause, prevent osteoporosis, and reduce the risk of heart disease. Hormone Response Element (HRE) stretch of DNA that responds to an activated receptor complex. Hypophysis see pituitary gland. Hypospadias displacement of urethral opening from the tip to the ventral side of the phallus. Hypothalamus a part of the brain that regulates many basic body functions (e.g., temperature, appetite, reproduction). In Vitro experiment conducted in an artificial environment (etiology: "in glass"). In Vivo experiment conducted using a whole organism. Masculinization the transformation of a structure (or behavior) to that typical of the male of the species. Meta-Analysis the compilation and subsequent analysis of a large collection of individual studies for the purpose of integrating the findings. back to top Negative Feedback regulatory process that reduces the output of a system, such as the action of heat on a thermostat to limit the output of a furnace. Neuroendocrine involving both the nervous and endocrine systems. Neurohormone a hormone produced by the brain. Neurohypophysis 1) posterior lobe of the pituitary. 2) stores and releases oxytocin and vasopressin, which are synthesized by neurons in the hypothalamus. Neurosteroid steroid produced in the brain. Oocyte egg or sperm. see gamete. Organizational effect permanent effect of hormone in developing organism that determines the cellular response to hormones after development (as opposed to activational effect). Ovary 1) female gonad. 2) produces oocytes (eggs) and hormones (estrogen, progesterone) necessary for reproduction. Peptide a natural or synthetic compound containing two or more amino acids linked together by peptide bonds. Phytoestrogen plant-made compound that mimics estrogen activity. Pituitary Gland 1) located at the base of the brain. 2) secretes hormones in response to inputs from the hypothalamus. Placebo 1) a substance that has no chemically relevant effect on a test subject. 2) often given to members of the control group during experimental trials that test the effects of a drug or other substance. Positive Feedback regulatory process that increases the output of a system. Pulsatile Release a periodic (non-continuous) release of hormone. both the amplitude and frequency of pulses are subject to feedback regulation. Randomized 1) not ordered. 2) a method to reduce bias in experimentation (e.g., a randomized trial). Releasing Hormone 1) a chemical that controls the production and release of other hormones. 2) usually refers to hypothalamic hormones that target the pituitary gland. back to top Seasonal Breeder an animal that produces offspring only during particular times of year. SERM Selective Estrogen Receptor Modulator, such as tamoxifen, which exhibits tissue-selective effects. Sexual Differentiation the process by which a developing individual assumes the characteristics of either a male or a female. Sexual Dimorphism having two distinct forms (e.g., differences in shape, size, coloring) of individuals within the same species, based on the gender of the individual. Steroid 1) molecule synthesized from cholesterol. 2) contains cyclopentenoperhydrophenanthrene nucleus. Stilbene 1) an aromatic hydrocarbon (C14 H12), produced by plants, often used as a phosphor and in making dyes. 2) backbone structure of several compounds with estrogenic activity (e.g., DES, resveratrol). Stimulatory hormone a chemical released from the pituitary gland that elicits a response in a target organ. System 1) orderly, interconnected parts. 2) must be defined by a modifier (e.g., endocrine system). Testis 1) male gonad. 2) produces sperm and hormones (testosterone) necessary for reproduction. back to top |