L10/11 Flashcards
State of disharmony or of threatened homeostasis
stress
Stressors can be ___, ____ or _____. They can be a ___ threat, or a ____ threat to homeostasis.
physiological, environmental, psychological, real, perceived
When under stress, ____ ___ becomes prioritized towards returning the body to homeostatic ___. Systems non-essential to ____ ___ are inhibited, which depends on the stressor. Some example systems are those for ____, _____, ___ function, and ____ cognition. if homeostatic disturbances require more energy than is readily available, survival becomes ____
energy use, steady-state, immediate survival, growth, reproduction, immune, higher-order, compromised
Systems involved in mediating stressors are _____, _____ / _____ neurotransmitters, _____ and _____ hormones. These operate as a ____, interactive network that can either ____ or _____ one another. The activity of these endocrine, nervous, and immune systems are influenced by an individual’s ____ and ____ makeup, developmental _____, social factors, and ____ state.
glucocorticoids, sympathetic, parasympathetic, cytokines, metabolic, nonlinear, up-regulate, down-regulate, psychological genetic, history, behavioural
a suite of physiological and behavioural responses that help to re-establish homeostasis
stress response
the core stress response is relatively ______ (ie. many stressors elicit the same stress response). However, the ___ and ___ of the stress response and it’s ____ effects can vary.
nonspecific, pattern, magnitude, long-term
the stress response is modulated by multiple mediators such as ____, DA, 5-HT, ____, ______, orexin, ____, corticosteroids, neurosteroids, and _____.
NE, CRH, vasopressin, dynorphin, urocortins
The components that govern the stress response are influenced by the ___, ___ and ___ of the stressor, as well as the ___, ___, _____ background, and ___ of the individual
duration, type, context, age, sex, genetic, gender
the _________ system involves ____ from the adrenal medulla. This system is ____, _____, short-term, involves a ____ response, and is _____. It results in increased gluconeogenesis, _____, _____, heart rate, and decreased ___ and ____ secretions
sympathetic-adrenal-medullary, epinephrine, immediate, fast-acting, fight-or-flight, nonspecific, glycogenolysis, vasoconstriction, digestion, gastrointestinal
The ____ axis involves ____ released from the adrenal cortex, is ____, ____ and is designed to ___ with the stressor. Activation results in decreased ____, ___, ___ and ____, and increased HPA _____ _____, and ____
HPA, glucocorticoids, slow acting, long-term, cope, digestion, immunity, growth, reproduction, negative feedback, neuroplasticity
The locus coeruleus is a ____ ____ nucleus that is the primary source of ___ in the brain. This NT can be released into the cortex as well, where it may exhibit higher order _____, as well as the ____
small brainstem, norepinephrine, cognition, periphery
The LC and the ___ ____ activate the _____ _____ in the spinal cord.
lateral hypothalamus, preganglionic fibers
The nerve pathway involves the _____ outputs from the preganglionic fibers to the ____ receptors on the peripheral nerves in the ____ ____, which release _____ from their postganglionic fibers onto the target organs such as ___ ___, cardiac muscle, and glands.
acetylcholine, N2, proximal ganglia, norepinephrine, smooth muscle
The hormone pathway involves the release of ___ from the preganglionic fibers to the ____ ____ chromaffin cells, which in turn release ______ / _____ into the blood, to reach ___ and ___ receptors on target organs
acetylcholine, adrenal medulla, norepinephrine, epinephrine, beta, alpha
to summarize the hormone and nerve pathways, acetylcholine makes the adrenal medulla release ____ into the bloodstream, while ___ ___ release synaptic norepinephrine
epinephrine, postganglionic fibers
Catecholamines like ___ and ____ are involved in fight, flight and freeze response
adrenaline, noradrenaline
Epinephrine and norepinephrine are involved in the immediate, ____ response. Release results in increased __ ___, ___ __, breathing rate, ____ ___, and metabolic rate. It also leads to changes in blood flow patterns which promote increased ___ and decreased _____ system activity
short term, heart rate, blood pressure, blood glucose, alertness, digestive
It was found in a study that there was a steady increase of ____ leading up to a phD defence, a transient peak on the day of, and a return to baseline __ days after
epinephrine, 4
The ___ neurons of the hypothalamus release ____ and _____, which triggers transcription of the ___ gene in the anterior pituitary. ____ ____ cleaves the gene into _______, which travels to the adrenal cortex to produce _____ and _____.
PVN, CRH, AVP, POMC, prohormone convertase, ACTH, glucocorticoids, mineralocorticoids
____ takes logner to peak in blood than ACTH after a stressor
cortisol
Glucocorticoids include ___ and ____. Rodents do not have cortisol
cortisol, corticosterone
___ is an example of a mineralocorticoid
aldosterone
When ACTH binds to the ______ receptor, adenylyl cyclase, cAMP, and protein kinase A all ______. This increases ____ uptake, the number of ____ _____ _____ receptors such as scavenger receptor B1, production of _____ lipase, and ______. It also stimulates transcription of the cholesterol side chain ____ _____, and upregulates ________ enzyme, which shifts steroidogenesis pathway towards glucocorticoid production
melanocortin 2, increase, cholesterol, membrane high-density lipoprotein, hormone-sensitive, star, cleavage enzyme, 3beta-HSD
catalyzes conversion of cholesterol ester to cholesterol
hormone-sensitive lipase
transports cholesterol to mitochondria
star
the mineralocorticoid and glucocorticoid receptors are widely distributed in the ____ and ___. They can be ____ or ______, the latter taking longer due to gene transcription. ____ have higher affinity for glucocorticoids than _____.
CNS, periphery, membrane-bound, cytosolic, MRs, GRs
Activation of cytosolic MRs results in slow _____ regulation of multiple genes, nearly _____ at resting and ____ corticosterone levels. There is increased activity in the ___ and less activity in the evening. This receptors maintains ____, setting the threshold for the stress response to prevent ____ and sustain ____
transcriptional, continuously, basal, morning, viability, maladaptivity, homeostasis
Activation of MR membrane receptors results when stress occurs and ____ bind to the MRs. There is a rapid, nongenomic increase in ______ release probability that happens in ____. Action of this receptor occurs shortly after the stressor as long as corticosterone is ____, and results in enhanced brain activity in certain limbic areas like the ____.
glucocorticoids, glutamate, minutes, corticosterone, amygdala
Once glucocorticoids are finished binding to the MRs and have ____ them, they bind to their own cytosolic GRs. This results in slow transcriptional regulation, and occurs in ____ after the stressor, when corticosterone is ____ again. This results in the ____ of brain activity, preservation of ___ information, and storage for future use
saturated, hours, low, normalization, encoded
Glucocorticoids and mineralocorticoids on a whole promote a ______, ___ ____ response
slower, longer lasting
Mineralocorticoids are involved in ___ and ___ retention, as well as increased blood ___ and ____
sodium, water, volume, pressure
Glucocorticoids are involved in converting ___ and ____ to glucose, or breaking it down for energy, increasing ____ _____, suppressing the ____ system, and changing ___
fats, proteins, blood glucose, immune, appetite
Mineralocorticoids and glucocorticoids inhibit _____, ____, and ___ production as negative feedback
POMC, PC1/3, ACTH
Glucocorticoids are transported in the blood bound to ____ proteins such as ____ ___ __ and _____. these prevent their ___ as well. CBGs are synthesized and secreted from the ____, and their concentrations are regulated by ____. From ELISA and RIA, it was found that 80-90% of glucocorticoids were bound to CBG, ____% were bound to albumin, and _____% were free
transport, corticosteroid binding globulin, albumin, degradation, liver, estrogens, 10-15, 3-5
In the SAM model, the first stage, _____ consists a brief period of low stress resistance, then a ____. The ____ is activated, and a conditioned reaction to the stressors results in a ___, ___ or ____ response. There is increased heart rate, blood pressure, and ___ ___, a loss of ____, racing thoughts, and fear and ____
alarm, rise, amygdala, fight, flight, freeze, muscle tension, focus, anxiety
The second stage of the SAM model is _____, and involves the _____ axis response, increased ___ ____, by physical and mental ______, and a seeking of _____ by the body. This results in poor ___, low ___, unstable ___, mental ___ and high emotional ____.
resistance, HPA, stress resistance, coping, homeostasis, sleep, immunity, mood, fatigue, reactivity
The last stage of the SAM model is ____, in which there is a ___ in stress resistance, when demands are overwhelmed the adaptive resources are fully _____. The body is in exhaustion, resulting in ____ ___, poor health, mental and ___ decline, feeling ___, and ____, as well as mood disorders
exhaustion, decrease, depleted, chronic fatigue, cognitive, numb, detached
Our body’s stress response is usually ____ and helps us adapt to changes in our environment. However, eventually, our bodies ___ ___.
beneficial, burn out
acute stressors that lead to healthy, moderate stress responses that are beneficial
eustress
chronic stressors that lead to an extended access stress response that becomes pathological
distress
An acute stressor lasts from ____ to ____. If it is a moderate stressor, there is _____, whereas if it is an intense stressor, there is _____. If there is a ____ stressor, there is damage.
minutes, hours, enhancement, suppression, traumatic
A chronic stressor that lasts for days to months can result in _____ ____, and loss of ____
adaptive plasticity, resilience
A chronic stressor that lasts for months to years can result in a decline of resilience with ___, and a vulnerability to ___ ___
age, permanent damage
The response to acute vs chronic stress is the same, but the ____ key. For example, acute stress results in increased _____ tone, while a pathological stressor results in ____. An acute stress may also result in enhanced _____, but accelerated ___ _____ during aging.
duration, cardiovascular, hypertension, cognitition, neural degeneration
There is a ____ relationship between psychological stress and depression. ______% of patients with MDD experience disturbances of the HPA system. Many patients have ______, heightened cort levels even at baseline due to disturbances of a negative feedback loop, and flattened ___ _____, resulting in a smaller ___ of CORT fluctuations throughout the day
bidirectional, 40-60, hypercortisolemia, circadian rhythm, range
Patients with MDD also show significant _____ atrophy, the severity of which correlates with the _____ of depression, not age. This is linked to poorer ______ memory and performance on tasks of _____ _____ such as the ___ ___ ___ test
hippocampal, duration, hippocampal-dependent, cognitive flexibility, wisconsin card sort
In depression, impaired _____ signalling leads to an attenuation of the ___ ____ ___, resulting in __ and ___ overactivity in the hypothalamus and increased ____ release from the anterior pituitary gland. This comes from a downregulation of the ____ and ____ receptors in the hypothalamus and pituitary where CORT normally binds to, resulting in less effective reduction of CORT release.
corticosteroid, negative feedback loop, AVP, CRH, ACTH, mineralocorticoid, glucocorticoid,
Normally giving a synthetic cortisol such as ___ will act on the negative feedback loop to minimize _____ CORT release. this is _____ in those with MDD.
DEX, endogenous, blunted
The glucocorticoids released from the HPA axis can also bind to receptors on the _____, which both inhibits and excites the PVN, the amygdala, which ___ the PVN, produces ____, and enhances CORT release, and the hippocampus, which ___ the PVN by furthering the negative feedback loop via glucocorticoids. The hippocampus and amygdla are rich in ___ and ___
PFC, excites, CRH, inhibits, MRs, GRs
Normally the hippocampus inhibits the ___, ___ and ____. In response to a stressor, the LC releases ____ into both circulation and the hippocampus. The NE ____ hippocampal projections to these three regions, resulting in increased activity of these regions. ___ and NE from the LC also enhances the activity of the _____, which excites the _____, leading to more CORT release
PVN, amygdala, LC, norepinephrine, inhibits, CORT, amygdala, PVN
The ___ and ___ of cortisol as well as the receptor ___, __ and _____, all contribute to the stress response
timing, concentration, type, density, distribution
Electrophysiology with ____ __ ___ ____, involves a whole brain tissue that is sectioned and placed in a ____ that keeps the cell alive. Using a glass ____, an individual cell ___ is poked to obtain the cytoplasmic solution, from the which the voltage can be measured
whole-cell patch clamp voltage, fluid, pipette, membrane
When hippocampal frequency is measured right after CORT treatment, neurons are ______. A 1-4 hour delay brings this back to ____. The same results are seen with the amygdala, however, the neurons are still more excitable after a ____. If there are 2 CORT exposures, both lead to _____ increases in excitability in the hippocampus, whereas only the ___ treatment has an effect in the amygdala.
hyperexcitable, baseline, delay, transient, first
This increased excitability in the amygdala and hippocampus are driven by cort acting on ____. In any brain region, these are activated ____, _____ MRs activate the ___ pathway, resulting in increased probability of release of glutamate vesicles. Post-synaptic MRs diffuse ______ receptors to the postsynaptic density and inhibit ___ channels. The net effect is an increase in excitability
MRs, first, presynaptic, ERK, AMPA, K+
Decreased excitability is driven by corticosterone acting on ______, when all MRs are saturated but there is still corticosterone present. Postsynaptic GRs activate the ____ pathway and triggers the release of _____ ___ and ____. These will travel back to ______ _____ receptors, and inhibit the release of ___ vesicles, resulting in a decrease in excitability.
GRs, cAMP, endocannibinoids 2-AG, AEA, presynaptic endocannabinoid, glutamate
The ____ of MRs and GRs decide whether there is an increase or decrease in excitability
distribution
When rats must suppress the innate behavior to go to a dark space associated with a foot shock
passive avoidance task
in the passive avoidance task, the time to return to the dark chamber
retention latency
In the passive avoidance task, giving ___ to rats made them show ___ passive avoidance. ___ lesions abolished passive learning, while ____ lesions did not have an effect. Thus, DEX must act within the BLA to ____ learning. Infusion of a ____ __ _____ into the BLA but not the CeA resulted in improved learning
DEX, stronger, BLA, CeA, enhance, glucocorticoid receptor agonist
The HPA axis development begins in the ____ state and continues to develop across the lifespan. In the neonatal stage, there is a _____ stress response, with ___ circulating CORT and ACTH, and an inability to elicit the stress response. Severe _____ might trigger faster ____ of the HPA axis to elicit a stress response. Pups that were deprived of their ____ had a stress response during the restraint stress test.
embryonic, hyporesponsive, low, trauma, maturation, mothers
In adolescence, there is a ______ stress response, with a higher ____ peak, and a ____ return to baseline. There is also attenuated stress _____. In pre-pubertal animals ____ increases in response to stress and takes longer to return to baseline than adult animals. Moreover, while a ____ stressor results in attenuated stress response in adults, this is not seen in adolescents
hyperresponsive, CORT, protracted, adaptation, CORT, homotypic
In adulthood there is both an ____ stress response and _____.
efficient, adaptation
Estradiol has ____ effects on HPA function. The estrogen responsive element binding on the CRH gene ____ CRH production. During _____ (when estradiol is at it’s peak) there is a peak in ___ and ____. Estradiol also increases CORT release from the ___ ____.
facilitatory, increases, proestrus, ACTH, CORT, adrenal cortex
Testosterone has _____ effects on HPA function, as androgen receptor element binding on the CRH gene ____ CRH production, and testosterone decreases CORT release from the adrenal cortex.
inhibitory, decreasing
Females exhibit ____ CORT response to stress and higher CORT levels at ____. They also show a greater ___ in CORT release across the day compared to males.
greater, baseline, variation
____ amplifies CORT response to acute restraint stress in males, with a ____ return to baseline
castration, protracted
the menstrual cycle phase alters ____ ____ ____. This is due to different amounts of estrogens circulating during ____ (higher) vs. ____ (lower) phases of the cycle. There is less ____ _____ during the luteal phase than the follicular phase
HPA negative feedback, follicular, luteal, DEX-induced suppression
