Juxtaglomerular apparatus, Biology

Assignment Help:

Juxtaglomerular Apparatus

The autoregulation of renal blood flow involves a neuroendocrine mechanism related to the juxtaglomerular apparatus in the kidney.

1896_Juxtaglomerular apparatus.png

 Figure: Structure of the juxtaglomerular apparatus in mammals

When the afferent arterial blood pressure is low, the stretch sensitive receptors of the arterioles initiate nerve impulses which induce the secretion of a proteolytic enzyme called renin by the juxtaglomerular cells into the blood. This enzyme causes the release of a decapeptide called angiotensin-I from a large globular plasma protein known as angiotensinogen. Another proteolytic enzyme from the plasma, the converting enzyme, removes two amino acids from angiotensin-I to form an octapeptide called angiotensin-II. Angiotensin-II is about 200 times more powerful than norepinephrine in its lasopressor activity. It increases the blood pressure by two mechanisms. Firstly, it acts on the smooth muscle of the arterioles and causes strong vasoconstriction. Secondly, it stimulates the secretion of aldosterone by the adrenal cortex. Aldosterone enhances the uptake of Na+ by the kidney tubules and hence causes a rise in the plasma Na+ level. This results in an increase in the extracellular fluid volume and consequently an elevation in blood pressure. Angiotensin-II is degraded by an enzyme called Angiotensinase, present in plasma.


Related Discussions:- Juxtaglomerular apparatus

Animal around us, #question.what are the reason that arthropodans are abund...

#question.what are the reason that arthropodans are abundant in nature.

Polyinvagination or ingression, PO L YIN V AGIN A TIO N OR INGRESSIO...

PO L YIN V AGIN A TIO N OR INGRESSION - This is found in discoblastula and periblastula. In it the blastomeres of the blastoderm divide and form new blastomeres wh

State the series of stimuli, State the series of stimuli ERPs a series ...

State the series of stimuli ERPs a series of stimuli such as tones or light flashes are presented to the participant, and the raw EEG for a precise one or two second period fol

Phylogeny and Evolution, While studying evolution, a student comes across a...

While studying evolution, a student comes across a cladogram that includes clades like amphibia, reptilia, aves, and mammalia. What must be the basal clade?

Explain about freezing point - properties of solutions, Freezing Point - Pr...

Freezing Point - Properties of Solutions The freezing point of a material is the temperature at which it changes from a liquid to a solid. A liquid freezes when its vapour pre

Causes of extinction, CAUSES OF EXTINCTION - 1 .       HUNTING - ...

CAUSES OF EXTINCTION - 1 .       HUNTING - Man started hunting wild animlas for food and safety trade and fun. It may be subsistence hunting, commercial hunting and sp

List the routine treatment sequence for an implant patient, List the routin...

List the routine treatment sequence for an implant patient. The different phases are - Preliminary treatment - Stage I surgical phase - Stage II surgery and Prosthetic

Define nutritional needs during pregnancy, Define Nutritional Needs during ...

Define Nutritional Needs during Pregnancy? It must be evident by now that several physiological changes occur in the body of an expectant mother and that malnutrition can' adve

Death and its significance, DE A T H - It is universal. It is ...

DE A T H - It is universal. It is last event in the degenerative process of ageing. It involves widspread cell break down & cell death. There is no heart beat, n

Zoonotic diseases-japanese encephalitis, Japanese encephalitis Japanes...

Japanese encephalitis Japanese encephalitis (JE) is a mosquito-borne encephalitis and is caused by  flavivirus belonged to the family Flaviviridae. It is a zoonotic disease, i

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd