hormones Flashcards
the synthetic derivatives of the male sex hormone, testosterone
anabolic steroids
chemical messengers that are synthesized, stored, and released into the blood by the endocrine glands and certain other cells
hormones
the study of the interactions between the nervous system and the endocrine system
neuroendocrinology
following stimulation, endocrine glands release peptide hormones to hormone specific receptors located…
on the surface (of the target tissue cells)
following stimulation, endocrine glands release steroid hormones and thyroid hormones into the blood which carries the hormones to hormone-specific receptors located…
in the nucleus of the target tissue cells
instance where instead of being released into the bloodstream, the hormone is released into the cell that secretes it
autocrine secretion
instead of being released into the bloodstream, the hormone is released to interact with adjacent cells
paracrine secretion
secreted by anterior pituitary gland, this hormone stimulates insulin-like growth factor 1, protein synthesis, growth and metabolism
growth hormone
secreted by the anterior pituitary gland, this hormone stimulates glucocorticoids in the adrenal cortex
adrenocorticotropic hormone
secreted by the anterior pituitary gland, this hormone stimulates analgesia
beta-endorphin
secreted by the anterior pituitary gland, this hormone stimulates thyroid hormone synthesis and secretion
thyroid-stimulating hormone
secreted by the anterior pituitary gland, this hormone stimulates growth of the follicles in ovary and seminiferous tubules in testes; stimulates ovum and sperm production
follicle-stimulating hormone
secreted by the anterior pituitary gland, this hormone stimulates ovulation and secretion of sex hormones in ovaries and testes
luteinizing hormone
secreted by the anterior pituitary gland, this hormone stimulates milk production in mammary glands, maintains corporalutea and secretion of progesterone
prolactin
secreted by the anterior pituitary gland, this hormone stimulates melanocytes, which contain the dark pigment melanin
melanocyte-stimulating hormone
secreted by the posterior pituitary gland, this hormone increases contraction of smooth muscle and reabsorption of water by kidneys
antidiuretic hormone
secreted by the posterior pituitary gland, this hormone stimulates uterine contractions and release of milk by mammary glands
oxytocin
secreted by the thyroid gland, this hormone stimulates oxidative metabolism in mitochondria and cell growth
thyroxine
secreted by the thyroid gland, this hormone reduces calcium phosphate levels in blood
calcitonin
secreted by the parathyroid glands, this hormone increases blood calcium; decreases blood phosphate; stimulates bone formation
parathyroid hormone
secreted by the pancreas, this hormone stores glycogen and promotes glucose entry into cells; involved in protein synthesis
insulin
secreted by the pancreas, this hormone increases blood glucose levels
glucagon
secreted by the adrenal cortex, this hormone inhibits amino acid incorporation into proteins; stimulates conversion of proteins into carbohydrates; maintain normal blood sugar level; conserve glucose; promote use of fat
glucocorticoids (cortisol, cortisone, etc)
secreted by the adrenal cortex, these hormones increase body fluids via sodium-potassium metabolism
mineralocorticoids (aldosterone, deoxycorticosterone, deoxycorticosterone, , etc)
secreted by the liver, these hormones increase protein synthesis in cells
insulin-like growth factors
secreted by the adrenal medulla, this hormone increases cardiac output; increases blood sugar and glycogen breakdown and fat metabolism
epinephrine
secreted by the adrenal medulla, this hormone has properties of epinephrine; also constricts blood vessels
norepinephrine
secreted by the adrenal medulla, these hormones enhance immune cell function, anagesia effects
proenkephalin fragments (eg, peptide F)
secreted by the ovaries, these hormones stimulate development of female sex characteristics
estrogens
secreted by the ovaries, this hormone stimulates development of female sex characteristics and mammary glands; maintains pregnancy
progesterone
secreted by the testes, this hormone stimulates growth; increases in protein anabolism, and development and maintenance of male sex characteristics
testosterone
secreted by the heart, this hormone regulates sodium, potassium and fluid volume
atrial peptide
secreted by the kidneys, this hormone regulates kidney function, permeability, solute
renin
the study of the neural, endocrine, and immune systems
neuroendocrine immunology
hormones that promote tissue building (eg, insulin, insulin-like growth factors, testosterone, and growth hormone)
anabolic hormones
hormones that degrade cell proteins (eg, cortisol and progesterone)
catabolic hormones
these proteins can go through a change in their molecular structure from Type IIx to Type II a heavy chain proteins in response to resistance training.
myosin heavy-chain (MHC) proteins
the most prominent resistance training adaptation
an increase in the amount of a muscle’s contractile proteins: actin and myosin
also an adaptation to resistance training: these proteins must be synthesized before the contractile proteins to provide structure and orientation for the contractile proteins
noncontractile proteins
the signal from a hormone (and thereby its effect) is relayed only to cells that express the __________for that specific hormone
receptor
binding proteins for growth hormones are an example of which form of receptor
mobile receptors
receptors integrated into the cell membrane are _______
polypeptide receptors
receptors on the regulatory elements of the DNA are
steroid receptors
the principle that a given hormone reacts with a specific receptor is ___________
lock-and-key theory
though only one hormone has exactly the right characteristics to react with a specific receptor, if the receptor can partially react with other hormones, it is said to have _____
cross-reactivity
sites at which substances other than hormones can enhance or reduce the cellular response at a receptor
allosteric binding sites
when further adaptation is no longer possible and the receptor becomes nonresponsive to a certain hormone, this is called
downregulation
the number of hormone _________ can increase or decrease as an adaptation to exercise training
receptors
these hormones are fat soluble and can passively diffuse across the sarcalemma of a muscle fiber. example: testosterone
steroid hormones
these hormones are made up of amino acids and include growth hormone and insulin
polypeptide hormones
3 major signalng pathways used by polypeptide hormones
(1) cyclic adenosine monophosphate-dependent (AMP) signaling pathway; (2) cytokine-activated JAK/STAT signaling pathway; (3) prototypical growth factor, mitogen-activated signaling pathway
acute hormonal secretions in response to heavy resistance exercise
(1) provide information to body regarding amount and type of physiological stress: epinephrine, (2) metabolic demands of exercise: insulin (3) need for changes in resting metabolism
summarize the hormonal adaptation to heavy resistance exercise
the specific force produced in activated fibers stimulates receptor and membrane sensitivities to anabolic factors, including hormones, which lead to muscle growth and strength changes.
factors affecting hormonal interaction with muscle tissue
(1) exercise acutely increases blood concentrations of hormones so probability of interaction is greater; (2) because adaptations to resistance training are typically anabolic, recovery mechanisms are related to increases in cell size; (3) mistakes in exercise prescriptions can result in a greater catabolic effect or an ineffective exercise program
hormonal changes in peripheral blood
(1) fluid volume shifts; (2) tissue clearance rates (3) hormonal degradation; (4) venous pooling of blood; (5) interactions with binding proteins in the blood
adaptations in the endocrine system
(1) amount of synthesis and storage of hormones; (2) transport of hormones via binding proteins;(3) time needed for the clearance of hormones through liver and other tissues; (4) amount of hormonal degradation that takes place over a given period of time; (5) how much blood-to-tissue fluid shift occurs with exercise stress; (6) how tightly the hormone binds to its receptor (receptor affinity). this is an uncommon response to exercise training; (7) how many receptors are in the tissue; (8) the magnitude of the signal sent to the cell nucleus by the H-RC or secondary messenger; (9) the degree of interaction with the cell nucleus (which dictates how much muscle protein to produce)
primary anabolic hormones
(1) testosterone; (2) growth hormone; (3) insulin-like growth factors;
the primary androgen hormone that interacts with skeletal muscle
testosterone
in men, large muscle group exercises affect serum total testosterone levels
acutely increase serum testosterone levels
(1) decreases glucose utilization, (2) decreases glycogen synthesis, (3) increases amino acid transport across cell membranes, (4) increases protein synthesis, (5) increases utilization of fatty acids, (6) increases lipolysis (fat breakdown), (7) increases availability of glucose and amino acids, (8) increases collagen synthesis, (10) stimulates cartilage growth, (11) increases retention of nitrogen, sodium, potassium, and phosphorus, (12) increases renal plasma flow and filtration, (13) promotes compensatory renal hypertrophy, (14) enhances immune cell function
the main physiological roles of growth hormone
how to stress the body to increase growth hormone levels in serum
(1) few reps (2) greater resistance (3) shorter rest periods
70-amino acid polypeptide secreted by the liver:; mediates effects of growth hormone; once stimulated by growth hormone, it takes the liver 8-29 hours to synthesize IGFs;
insulin-like growth factor I (IGF-I)
67 amino acid polypeptide secreted by the liver; mediates effects of growth hormone; once stimulated by growth hormone, it takes the liver 8-29 hours to synthesize IGFs
insulin-like growth factor II (IGF-II)
this IGF has prolific role in protein anabolism
IGF-I
portion of adrenal gland that is stimulated by the nervous system and provides the faster response
adrenal medulla
portion of the adrenal gland that is stimulated by adrenocorticotropic hormone (ACTH) from the anterior pituitary gland
adrenal cortex
this glucocorticoid is a primary signal hormone for carbohydrate metabolism and is related to glycogen stores in the muscles. when glycogen concentrations are low, other substrates (proteins) must be catabolized to produce energy
cortisol
(1) converts amino acids to carbohydrates; (2)increases level of protealytic enzymes (enzymes that breakdown proteins); (3) inhibiting protein synthesis. still being studied: Cortisol appears to have greater catabolic affects on Type II muscle fibers because they have greater protein content. Cortisol appears to help control the degradation of Type I muscle fibers
role of cortisol
Cortisol is produced at its greatest levels when resistance exercise has________
short rest periods and high volume and uses large muscle groups
epinephrine, norepinephrine, and dopamine are _________ . They help express acute strength and power (fight or flight)
catecholamines
(1)increase force production via central mechanisms and increase metabolic enzyme activity; (2) increase muscle contraction rate; (3) increase blood pressure; (4) increase energy availability; (5) increase blood flow; (6) augment secretion rates of other hormones such as testosterone.
role of catecholamines
varying training protocols allows the adrenal gland to engage in recovery processes and prevent secondary responses of cortisol
preventing overtraining
