Hormones and the Brain (kapitel 5) Flashcards
The word hormones, comes from the greek word horman, which means?
To excite.
A hormone is?
A chemical secreted by an endocrine gland that is conveyed by the bloodstream and regulates target organs or tissues.
Explain how endocrine communication happen, compared to the neurocrine (synaptic) communication.
In endocrine communication, the chemical signal is a hormone released into the bloodstream, to selectively affect distant target organs (p. 128).. In neurocrine or synaptic communication, the released chemical signal diffuses across the synaptic cleft and causes changes in the postsynaptic membrane (as we saw in chapter 3 and 4).
What is meant by autocrine communication?
A chemical signal that is secreted by a cell into its environment, and then feeds back to the same cell.
What does a peptide hormones consist of?
bonus; Can you name some peptide hormones?
Peptide hormones is a class of hormones, which consist of a string of amino acids. If the string of amino acids is long enough, it may be called a protein hormone.
(Insulin, Thyroid-stimulating hormone, Oxytocin and more on p. 131).
Complete the sentence:
“Steroids dissolve readily in lipids, so they easily..”
”.. pass trough membranes”. (#thelipidbilayer).
Hormones affect many everyday behaviors in humans and other animals. They exert these far-reaching effects in two ways, which are?
- Promoting the proliferation, growth, and differentiation of cells and ..
- by modulating cell activity.
“The relationship between behavior and hormones is..”
”.. reciprocal: Hormones change behavior, and behavior change hormones”.
How does neuroendocrine communication work?
Neuroendocrine cells are the interface between neurons and endocrine glands. In this way electrical signals are converted into hormonal signals, so:
Neuron -> neuronendocrine cell -> Bloodstream.
What is peptide hormones?
A class of hormones, molecules of which consists of a string of amino acids. If the string of amino acids is long enough, it may be called a protein hormone.
What is amine hormones?
(Also called monoamine hormones). A class of hormones, each composed of a single amino acid that has been modified into a related molecule, such as melatonin or epinephrine.
Explain what a second messenger is.
Its a slow-acting substance in a target cell that amplifies the effects of a synaptic or hormonal activity and regulates activity within the target cell.
So, when a hormone binds to a recepter, a second messenger inside the cell either alteres the cell function and/or creates multiple biological effects.
What characterizes steroid hormones?
For one, they typically act more slowly than protein or amine hormones. The specific actions, is determined by the receptors that reside inside the target cell. And also, by regulating gene expression, steroid hormones can affect a vast array of cellular processes.
What is meant by a nongenomic effect?
It is an effect of a steroid hormone that is not mediated by direct changes in gene expression.
Peter Bang har engang givet udtryk for, at en ganske speciel ting skal være anført på den første artikel han udgiver. Hvad er det, Peter gerne vil have anført?
At han er fra Randers.
What is a transcription factor?
A substance that binds to recognition sites on DNA and alters the rate of expression of particular genes.
What kind of messenger (thats a hint) is cyclic AMP and cyclic GMP?
A second messenger activated in target cells in response to synaptic or hormonal stimulation.
Explain the hormonal ‘negative feedback’ mechanism.
Output of the hormone feeds back to inhibit the drive for more of that same hormone (p. 136).
The Pituitary Gland is located just X to the hypothalamus. What is X?
Under.
The Pituitary Gland can be divided into two parts. What are they?
Anterior- and posterior pituitary gland
Where is the pituitary stalk located? And what does it mainly consist of?
It’s a thin piece of tissue that connects the pituitary gland to the hypothalamus and it mainly consists of axons and with blood vessels.
The Axons in the pituitary stalk leads information to? And the blood vessels in the pituitary stalk leads information to?
Axons = Posterior pituitary
Blood Vessels = Anterior pituitary
I Christians køkken hænger der et billede af en musikalsk duo der spiser burgere. Duo’en står bl.a. bag hits som “Can i Get Get Get” & “Shake Your Coconuts”. Hvad er navnet på duo’en?
Junior Senior.
The Posterior pituitary gland secretes mainly two principal hormones. What are they?
Oxytocin & (arginine) vasopressin.
The Supraoptic nucleus, is a hypothalamic nucleus containing.. ?
..neuroendocrine cells that send axons to the posterior pituitary to release oxytocin or vasopressin.
What is the main function of vasopressin?
It inhibits the formation of urine. (a terrific thing, if you are standing at a festival, in the middle of a crowd for example).
Oxytocin is involved in many aspects of.. ?
.. reproductive, sexual and parental behavior (like milk letdown reflex).
So, where is the oxytocin and vasopressin produced?
In the hypothalamus, in neuroendocrine cell bodies.
What does the median eminence refer to?
The midline feature on the base of the brain marking the point, at which the pituitary stalk exits the hypothalamus to connect to the pituitary. (bonus: It contains elements of the hypophyseal portal system). p. 141
The Hypophyseal portal system is a?
..Duplex system of capillaries spanning between the neurosecretory cells of the hypothalamus and the secretory tissue of the anterior pituitary. p. 141
As you might recall from a prior question.. The hormones in the anterior pituitary travel from the hypothalamus only a very short distance by axons, and then they travel to the anterior pituitary by?
Blood. (Which is also the title of a great album by Lianne La Havas).
What is the function of Tropic (Spoken: Tr(oe)pic) hormornes ?
They regulate endocrine glands throughout the body.
Name at least 3 of the 5 tropic hormones mentioned int the book. (p. 141).
Prolactin, Gonadotropic hormones (FSH and LH), Thyroid-stimulating hormone, ACTH, Growth Hormone. (To read about them specifically, see p. 142 - 143).
The hypothalamic neuroendocrine cells that synthesize the releasing hormones are themselves subject to two kinds of influence. Describe them.
- circulating messages; such as other hormones, bloodsugar and immune system.
- synaptic input: from many other brain regions.
Where is the adrenal cortex located?
Kind of on top of the kidney (p. 142).
Pause: Du sidder nu har set 35 kort omhandlende emnet hormoner. Hvis du sidder og tænker over hvorfor det overhovedet er spændende; Så se videoen på den anden side af kortet!
Derefter, god fornøjelse med resten af vendespillet!
http://www.nytimes.com/video/magazine/100000004110233/karl-ove-knausgaard-witnesses-brain-surgery.html
Where is the adrenal medulla located? And what hormones does it secrete?
It’s the inner core of the adrenal gland, which secretes epinephrine and norepinephrine.
What effect does the hormones epinephrine and norepinephrine have on the body?
Prepare the body for action (a classic fight or flight).
The adrenal cortex produces and secretes a variety of steroid hormones, collectively called?
Adrenocorticoids.
Other hormones secreted by the adrenal cortex are sex steroids, such as androstenedione
What does Thyroid hormones regulate?
Growth and metabolism.
What is aldosterone implicated in?
Its a mineralocorticoid hormone, secreted by the adrenal cortex, that induces the kidneys to conserve sodium ions.
Name to thyroid hormones.
Triiodothyronine and thyroxine (is released from the thyroid gland, that have widespread effects, including growth and maintenance of the brain.).
The Adrenal cortex secretes:
Glucocorticoids (corticosterone, cortisol), mineralocorticoids (aldosterone) and sex steroids
Its a bit fun that the peptide X appears to play an important role in governing the onset of puberty. X is?
Kisspeptin.
The pineal gland secretes an amine hormone called?
Melatonin.
The pineal gland is located?
Atop the brainstem and is in mammals overlain by the cerebral hemispheres. The pineal gland is also a single structure (there is no left or right hemisphere, as there often is with the brain).
Melatonin is secreted at a specific time. Is that true or false?
True. Almost exclusively at night. (Bonus; it is also used to treat jetlag).
