Flashcards
Hormones of the Kidney, Micturition and Control of Body Fluid
Flashcards do conjunto (74)
- 1What are the two consequences of an increases in osmolarity of the extracellular fluid?dehydration and thirst
- 2What hormone is released from the posterior pituitary in response to plasma omsolarity changes?Antidiuretic Hormone/Vasopressin
- 3How is a rise in plasma osmolarity detected?by osmoreceptors in the hypothalamus
- 4What action do osmoreceptors take to respond to osmolarity changes?regulate the release of ADH from neuroendocrine cells, which is stored in vesicles to be released from the posterior pituitary as needed
- 5What effect does excess fluid have on body fluid osmolarity?lowers body fluid osmolarity by diluting solutes in plasms
- 6At normal plasma osmolarity, is there any ADH in the blood?yes, allowing a response to increases and decreases in body fluid osmolarity
- 7What effect will an increase in osmolarity have on level of ADH?increases circulating levels of ADH and increases water reabsorption
- 8What effect will a decreases in osmolarity have on circulating levels of ADH?decreases levels of ADH and so decreases water reabsorption
- 9What effect does an increases in ADH have on urine production?prevents the excretion of urine
- 10What part of the nephron does ADH have an effect on?distal tubules and collecting duct
- 11What other change within the body can stimulate the release of ADH?a decrease in blood pressure increases ADH secretion
- 12How does an increase in ADH work to return blood pressure to normal levels?increases water reabsorption to reduce the osmolarity to restore blood pressure
- 13At what percentage decrease of blood pressure does it become a strong stimulus for ADH secretion?a decrease by over 10%
- 14Which factor, osmolarity changes and blood pressure changes, acts as a more effective stimulus for ADH response?osmolarity changes
- 15At levels that are higher than needed to concentrate urine, what effect does ADH also have?acts as a vasoconstrictor to increase blood pressure at its maximum secretion
- 16What two factors together allow the ECF to be diluted to lower osmolarity?conservation of water and the same solute excretion levels
- 17What does a change in ADH levels actually affect on a cellular structure level?the number of aquaporins expressed on the cell membrane (increases or decreases this amount)
- 18What time frame does ADH respond within to changes in osmolarity?within minutes
- 19What is the half life for ADH within the blood?15 minutes
- 20What happens to the ADH to be removed from circulation?removed by the kidneys or metabolised to allow further responses to be carried out
- 21What substance found in cigarettes affects ADH release?Nicotine increases ADH release (like morphine)
- 22How does diabetes insipidus affect ADH release?Central: removes control over osmolarity changes and so affects the production of ADH
Nephrogenic: receptors to ADH are not present on the collecting ducts so there is no renal response - 23What is the most important extracellular ion in terms of regulation of osmolarity?Sodium
- 24What system would be affected if total Sodium levels weren't regulated but osmolarity was maintained?Cardiovascular system; total body fluid might increase which would increase the strain on the CVS
- 25What percentage of the ECF osmolarity is made up by Sodium ions?94%
- 26What Sodium levels must be equalised to maintain a stable ECF volume?amount of Sodium ingested and the losses from the body
- 27What is the only body fluid that can be acted upon to regulate the volume and composition of ECF?plasma
- 28What hormone is the most important determinant of renal Na+ reabsorption?Aldosterone
- 29Where is Aldosterone produced?in the adrenal cortex (result of angiotensin II)
- 30What effect does Aldosterone have?stimulates the Na+ reabsorption in the distal parts of the nephron
- 31What ions does Aldosterone promote the secretion of?H+ and K+ via H+K+ATPase
- 32Besides from the distal tubule and collecting ducts, where else does Aldosterone promote Na+ reabsorption from?colon, gastric glands and sweat glands
- 33What overall effect does Aldosterone have on body fluid volume?increases body fluid volume
- 34What change in ionic composition of the plasma stimulates Aldosterone release?increase in K+
- 35What are the two most important changes within the body that stimulate Aldosterone release?change in plasma K+ concentration and a decrease in effective circulatory volume
- 36Via what system does a decrease in effective circulatory volume lead to an increase in Aldosterone levels?renin-angiotensin system
- 37What enzyme is produced by the juxtaglomerular apparatus when body Na+ is reduced?Renin
- 38What change in arterial blood pressure also induces the release of renin?a fall in arterial blood pressure
- 39What effect does Angiotensin II have on reabsorption?increases tubular reabsorption of salt and water
- 40How can sympathetic activity have an effect on Angiotensin II?an increase in activity leads to an increase in renin release (more angiotensin II and so aldosterone)
- 41Angiotensin II prioritises the perfusion of which organs?the brain and the heart
- 42What action does Angiotensin II have on afferent and efferent arterioles?constricts arterioles to reduce renal blood flow
- 43How does arteriolar constriction lead to increased reabsorption?the reduction in renal blood flow increases the oncotic pressure in blood leaving the glomerular capillaries and so favours water and salt reabsorption
- 44What is the only way in which Angiotensin II can actually increase Na+ content?by stimulating Aldosterone
- 45What enzyme, found in the endothelial cells of the lung, converts Angiotensin ! to Angiotensin II?Angiotensin converting enzmye (ACE)
- 46What treatment can be given for high blood pressure?ACE inhibitors
- 47What centre in the hypothalamus is also stimulated by Angiotensin II?thirst centre to increase the body fluid intake
- 48What substances are synthesised and released from cardiac atrial cells?Atrial Natriuretic Peptides
- 49What are ANP's released in response to?released in response to atrial stretch/increased extracellular volume
- 50What effect do ANP's have on Sodium and ECF volume?inhibit Na+ reabsorption and increase Sodium excretion to reduce ECF volume and blood plasma
- 51ANP's inhibit the production of which hormone involved in Sodium regulation?Aldosterone
- 52What action do ANP's have on afferent arterioles and what effect does this have in the kidney?vasodilation of afferent arterioles and increase the glomerular filtration rate
- 53Which ionic exchange is increased by Angiotensin II and where does this take place?Na+/H+ exchange in the proximal tubule
- 54How does Angiotensin II affect the GFR?reduces the GFR
- 55What effect does an increase in sympathetic activity have on Sodium filtration?decreases filtration
- 56Where in the nephron do osmotic diuretics act on?proximal tubule to decrease reabsorption
- 57What do Thiazide diuretics do and where do they have an effect within the nephron?block Na+ transporters in the distal tubule
- 58What do Loop diuretics do?inhibit Na+ re-uptake in the ascending limbs of the LoH, which reduces the gradient needed for Sodium reabsorption
- 59Where in the nephron do K+ sparing diuretics and Na+ channel blockers have an effect?in the collecting duct
- 60What hormone is produced in the kidney that stimulates red blood cell production?erythropoetin
- 61What is micturition?urination
- 62How does urine composition change once it leaves the renal pelvis?it doesn't - only in horses where mucus secretion in the ureter makes the urine slightly viscous
- 63How is urine transported from the kidneys to the bladder?moves as boluses via peristaltic contraction of smooth muscle
- 64What sphincter is involuntarily controlled and keeps the entrance to the urethra closed?the internal sphincter
- 65What autonomic activity causes the internal sphincter to remain closed?tonic sympathetic activity
- 66What form of innervation is responsible for keeping the external sphincter closed?tonic somatic activity
- 67How is a change in bladder volume detected?stretch-sensitive receptors in the walls of the bladder detect this
- 68What happens to sensory neurones as the bladder fills?an increase in pressure within the bladder causes an increase in activity of the sensory neurones
- 69What does an increase in parasympathetic activity have within the bladder?detrusor muscle contracts, bladder pressure increases, increased contractions, increased pressure etc
- 70As the contractions and pressure in the bladder increases, what eventually happens?decrease in somatic activity to the external sphincter, sphincter opens and the neck of the bladder dilates
- 71What is reflex emptying of the bladder an example of?positive feedback
- 72What does urine flow out of the bladder stimulate?stimulates urethra sensory cells to increase parasympathetic activity to the bladder muscles to allow complete emptying
- 73Where in the brain does voluntary suppression of urination originate from?cerebral cortex
- 74In newborn and untrained animals, what is urination a result of?urination is the result of a spinal reflex, which is determined by the amount of urine in the bladder at any given time
Informações
- Descrição
- Animal Disease 1 Veterinary Medicine FlashCards sobre Hormones of the Kidney, Micturition and Control of Body Fluid, criado por Louise Mason em 20-03-2017.
- Criado por
- Louise Mason
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