General Introduction Flashcards
Filtration barrier
Endothelium of capillaries, basement mb, foot processes of podocytes.
Endo- fenestrated, anionic glycoproteins
Basement- mesh work of fibrils, negative proteins, collagen
Podocytes- visceral layer of Bowman’s capsule.
Slit pores, nephrin.
Mesangial cells
Blood monocytes, MPS Close to glomerular capillaries Structural support to caps Secrete extra cellular matrix Prostaglandins and cytokines Phagocytic Contractile units, alter GFR Outside glomerulus called lacis cells, secrete renin and erythropoietin Immune complex mediated glomerular disease
What is JGA and it’s components
The thick ascending limb of loop of Henle, contact with same glomerulus, structural mod in tubule, afferent and eff arteriole.
Macula densa of thick asc limb
Juxtaglomerular cells (mod muscle cells of aff arterioles)
Lacis cells
Macula densa, JG cell, Lacis cell
MD: mod epi cell of loop, that passes through angle b/w aff&eff arteriole. Senses change in ionic comp, rate of flow, feedback signal
JG: epitheloid, mod vascular smooth muscle, renin
Lacis: in triangle b/w aff&eff and macula densa.
Renin and erythropoietin.
Renin angiotensin system
Renin- angiotensin to I, II to III.
Essential for reg of ECF, blood volume and blood pressure.
Increase: decrease blood volume, decrease Na+, increased symp, increase catecholamines, prostaglandins
Decrease: ADH, increased bp, increase na
Conditions of increase: hypovolemia, hyponatremia, hyperkalemia, dehydration, hypotension, standing, cirrhosis of liver, constriction of renal artery
Angiotensin II physiological actions
Peripheral: potent vasoconstrictor Secretion of aldosterone Direct release of NE Contraction of mesangial cells, decrease GFR Increase na, water reab from PCT Central: decrease baroreflex Stimulate thirst centre, circumventricular organ Increase ADH Increase ACTH Acts as neurotransmitter
