Vitamin D Council Glossary

# A B C D E F G H I J–K L M N O P R S T U V
An epidemic of infectious disease that spreads through populations across a large region, such as a continent, or even globally.
A cell's signaling of other cells by secreting a chemical that interacts with the receptors on nearby cells.
Parathyroid Glands
Small endocrine glands in the neck whose sole function is to regulate the body's calcium level for the proper functioning of the nervous and muscular systems.
Parathyroid Hormone (PTH)
Also called parathormone, parathyroid hormone is a hormone secreted by the parathyroid glands and the most important endocrine regulator of calcium and phosphorus concentration in extracellular fluid.
19-nor-1, 25-dihydroxyvitamin D2. A noncalcemic vitamin D analogue that is used in the treatment of secondary hyperparathyroidism.
Parkinson's Disease (PD)
Motor system disorder which results from the loss of dopamine-producing brain cells.
The origin of a disease and the chain of events leading to that disease.
Altered or caused by disease.
see pathology.
The study of the nature of diseases and of the structural and functional changes produced by them.
Peptide hormone
Hormone belonging to a class of peptides that are secreted into the blood stream and have endocrine functions in living animals.
Family of short molecules formed from the linking of various α-amino acids.
Inflammation of the pericardium, the most common symptom of which is chest pain.
Thin layer of tissue covering the outer surfaces of the heart, protecting it from tumors, infections, and possibly enlargment.
Peripheral Nervous System (PNS)
Contains only nerves, connects the Central Nervous System (brain and spinal cord) to the rest of the body. Composed of two major subdivisions: the Somatic Nervous System and Autonomic Nervous System.
Study of what a drug or substance does to the body.
Study of what the body does to a drug or substance.
Pharmacological dose
The minimum dose needed to make a drug medically effective in treating an illness.
The scientific study of drugs and their effects, especially in the treatment of disease.
The class to which an organism belongs as determined by the physical and behavioral characteristics of that organism.
Phosphorus, also Phosphate
Mineral macronutrient essential to all lifeforms. Phosphorus has a role in many bodily functions such as intracellular energy transfer, regulation of many biochemical processes, catalytic activity of enzymes, and oxygen dissociation from hemoglobin. The backbones of DNA and RNA are composed of phosphorus bound to sugars.
Physiological dose
The minimum dose needed to produce a physiological effect in the body.
The normal mechanical, physical, and biochemical processes of living things.
Pineal gland
Tiny endocrine gland situated at the center of the brain that secretes melatonin.
Pituitary gland
An endocrine gland that is composed of two distinct parts: the anterior and posterior pituitary. Together these two parts secrete a battery of hormones that influence all cells and affect all physiologic processes within the body.
Occurring in various distinct forms, multi-functional.
Polychlorinated Biphenyls (PCBs)
Organic compounds that have been shown to be carcinogenic, adversely impacting the environment and human health. Although a ban was placed on their production in the 1970s, PCBs are still present in the environment.
A small genetic change, or variation, that can occur within a person's DNA sequence.
A peptide consisting of 2 or more amino acids. Amino acids make up polypeptides which, in turn, make up proteins.
Essential dietary mineral and electrolyte. Normal body function depends on tight regulation of potassium concentrations both inside and outside of cells.
A glandular secretory product that is a precursor of a hormone but has little, or no, inherent biological potency itself.
The Prospective Epidemiological Study of Myocardial Infarction.
The process of cell maturation and self-definition through the acquisition of additional individual characteristics.
Any substance that can be converted to a hormone.
Prolactin (PRL)
Peptide hormone primarily associated with lactation.
A medication or treatment designed and used to prevent a disease from occurring.
Prospective cohort study
Research that follows over time groups of individuals who are similar in some respects, but different in others, and compares them for a particular outcome, such as disease. The study begins with a sample whose members are free of the disease under study.
Prostate gland
Exocrine gland of the male mammalian reproductive system.
Prostate-specific antigen (PSA)
A protein produced by normal prostate cells that plays an important role in fertility.
The basis for the major structural components of animal and human tissue, proteins are probably the most important class of biochemical molecules and are essential for life.
Digestion of proteins by cellular enzymes (called proteases) or by intramolecular digestion.
PubMed is a service of the US National Library of Medicine that includes over 16 million citations from Medline and other life science journals for biomedical articles dating back to the 1950s.

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