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

What is the plant hormone remarkable for stimulating, What is the plant hor...

What is the plant hormone remarkable for stimulating flowering and fruit ripening? What are the uses and practical inconveniences of that hormone? The plant hormone notable for

How many computers can access the ebook on, I usually study in the library ...

I usually study in the library on the schools computers so I will be accessing the eBook from many different computers throughout the semester. Is there a limit to how many compute

What is the constitution of the cartilaginous matrix, What is the constitut...

What is the constitution of the cartilaginous matrix? The cartilaginous matrix is made of collagen fibers, mostly collagen type II, and of proteoglycans, proteins associated to

What is placebo and nocebo, Problem 1: What is Placebo and Nocebo? Desc...

Problem 1: What is Placebo and Nocebo? Describe the significance of Placebo in clinical trials. Definition of placebo and Nocebo Significance of Placebo in clinical t

Cell, how does a cell work ?

how does a cell work ?

Trinomial system, who proposed trinomial system of classification? in ALLEN...

who proposed trinomial system of classification? in ALLEN modules ans is Huxley & Stricklandt but in AAKASH its given Lamarck so what is correct?

SOIL, WHICH SOIL WILL BE FRUIFUL FOR GROWING LENTILS AND OTHER PULSES

WHICH SOIL WILL BE FRUIFUL FOR GROWING LENTILS AND OTHER PULSES

Eubiont, Eubiont The origin of true life , eubiont from a pmtobiont inv...

Eubiont The origin of true life , eubiont from a pmtobiont involves the acquisition of three major features: 1) assembly of phospholipids and proteins into a cell membrane f

Nucleoplasm, NUCLEOPLAS M OR KARYOPLASM OR KARYOLYMPH OR NUCLEAR SAP N...

NUCLEOPLAS M OR KARYOPLASM OR KARYOLYMPH OR NUCLEAR SAP Nucleoplasm and cytoplasm name proposed by E. Strassburger . Chemical composition of nucleoplasm given by Kossel . Co

Define absorption, Define Absorption, transport and Excretion of phosphorus...

Define Absorption, transport and Excretion of phosphorus? As you have seen that food contains both organic and inorganic phosphorus, but most of it is absorbed in its inorganic

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