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

Define procedure for detection of chalk in flour, Define Procedure for Dete...

Define Procedure for Detection of Chalk in Flour Carry out the experiment following the procedure given herewith: 1. Take a teaspoon of flour in a test tube and shake it wit

Issues impacting health and development - inequity, Normal 0 fa...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

The trp operon, The trp (tryptophan) operon which is shown in the figure wi...

The trp (tryptophan) operon which is shown in the figure will have  five  structural  genes  encoding enzymes  for tryptophan  biosynthesis  with an upstream  Ptrp  (trp promoter)

0smosis, what is the difination of osmosis

what is the difination of osmosis

Explain stavudine, Explain Stavudine It can be given either in initial ...

Explain Stavudine It can be given either in initial combination therapy or after failure of regimens containing other NRTIs. Cross-resistance with zidovudine is frequent, ho

Determine about the degenerative diseases, Determine about the degenerative...

Determine about the degenerative diseases Immune responses in brain can quickly spiral out of control and cause further harm. In degenerative diseases such as Parkinson's, Alz

Explain pediculosis and scabies, Pediculosis and scabies  Phthirus pubi...

Pediculosis and scabies  Phthirus pubis (pubic lice), which can be found on eyelashes, back, axillary and leg hairs as well as pubic areas, and Sarcoptes scabiei infestation (s

Pre-embryonic development, Pre-Embryonic Development We had said in t...

Pre-Embryonic Development We had said in the starting of the unit that prenatal development can be divided into two phases, embryonic and foetal. The embryonic phase of devel

Bioluminescence, #question.which annelids shws bioluminescence .

#question.which annelids shws bioluminescence .

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