INNERRVATION OF BLOOD VESSELS AND HEART Flashcards
Integrated/ HMGO reductase inhibitors Statins causes Myopathy & muscle damage → renal failure in patient with renal dysfunction especially when combined with ?
Fibrates
or nicotinic acid
Ө HMGO reductase enzyme →
↓CE in the liver → ↑LDL
receptors → ↑ uptake of LDL
in the liver → ↓ plasma LDLCE
• ↓ TG & ↑ HDL
Bile acid sequestrates
Cholestyramine
Cholestipol
functions
Hypercholesterolemia
2. With statin (prevent ↑
endogenous CE synthesis)
or if statins are #
sympathatic NORADRENERGIC FIBERS
Arise from vasomotor centre affect alpah receptor in small arterires and ARTERIOLES and veins CASUING VC CANT STIMULATE VENULES AND CAPILLARIES !
SYMPATHATIC CHOINERGIC FIBERS ! From where they arise what are the functions ?
they areis from the hypothalamus and they are choinergic casuing release Ach CAUSING VD
WORK ON 4 ! 1 - EXERCISE 2-HYPERTENNSION 3- FEAR 4-CAROTID SINUS SSYNDROME##
Parasympathatic cholinergic fibers areis function ?
They arise CRANIOSACRAL
the 37910 1973 !
cranial nerves to the heart and brain and git causing VD incresing the flow to these organs
while sacral 234 casuing erection of blood vessels of !
TIP : VD AT LOCAL TISSUE CAUSING INCREASING BLOOD SYPPLY TO IT !
VC AT BLOOD VESSELS CAUSING THE HIGH VELOCITY OF BLOOD TO REACH THE TISSUE
SO WE NEED VC IN BVS SYSTEMIC AND VD IN BLOOD VESSELS LOCAL TISSUE TO INCREAE ITS BLOOD FLOW AND SUPPLY
تخيل انك مضيق خرطوم ماء وبترش الماء في حوض
فضيق الخرطوم هو الوعاء الضيق اللي هيوصل للعضو
والحوض هو الاوعية الدموية بتاعت العضو كلما زادت مساحة الحوض بالاتساع زاد الانسياب الدموي وكلما قلت مساحة الحوض قل الانسياب الدموي
Functions of arterioles ?
Reuglation of 2 !
the blood flow
the vasomotor tone 1
GR/ the the aretrioles regulate the vasomotor tone ?
beccause they are under effect of ne sympathatic fibers from the VMC
CASUING VASOMOTOR TONE ON IT SYMAPATHCRI TONE !
WHY BRAIN AND HEART HAVE LOWER VASMOTOR TONE?>
AS THEY ARE VITAL ORGANS SO THE BLOOD FLOW CANT DECRESR IN THEM
THE SKIN AND GIT AND RESTING SKELETAL MUSCLES HAS HIGEST VMC TONE ?
Because they are at rest not needing blood as git and skeletal muscles
tip : no VMC IN THE VEINS
In case of DEC BP THE VMC STIMULATED CAUSING arteriolar vasoconstriction the capillarirs increases abp how ?
Capillary flud shift resrve ! \
in case of aretriolar vc there ois high resitannce and the blood decrease in capillaries decrasing pressure so the fluid enter the capillary fronm ISF TO RAISE IT!
VMC + CASAUNG VENUOLCONSTRICTION VR INC INC COP INC ABP
lOSS OF VMC TONE DUE TO CRUSH INJURY IS NOT THE END OF THE CONSTRICON OF ARTERIOLES ?
BECAUSE THER IS INTENAL MYOGENIC VASOCNSTRICTION TONE IN ARETRIOLE !
Mention Cholestyramine mechanism
Bind with bile acid in the intestine → prevent its reabsorption to liver → ↓ bile acid in the liver → ↑ conversion of CE to bile → ↓ hepatic CE → ↑ LDL receptors → ↓plasma LDL-CE
- Combined hyperlipidemia
- Hypercholesterolemia
are the indications of ?
HMGO reductase inhibitors
Statins
Sim, Ator, Flu vastatin
the sympathatic NE outflow affect ?
samll arteris arteriole
capacitence vessel vein
SKELETAL MUSCLES AND SKIN VESSEL THE MAJOR EFFECTOR ON THE RESISTTANCE PERIPHERAL NOT RECEVING CHOLINERGIC PARA SYMP
SO PARA NOT AFFECT ABPgonist →
TIP : THE CHOLINE SYMAP VD SKELETAL BLOOD VESSELS WITHOUT INCREASED OXYGEN CONSUPTION
Lipoprotein lipase activators
Fibrates
Fenofibrate, Gimfibrozil قخمث
• PPAR-α receptor agonist → ↑activity of plasma lipoprotein lipase → hydrolysis of VLDL & chylomicrons →↓ serum TG • ↑ LDL uptake by the liver & كذلك يزود مستقبلات LDL ↑ HD
in case of fall in the arterial blood pressure what is the compensatory mechanism ?
The VMC will be stimulated casuing
1-vc of the arterioles casuein increafin tpr hr vr abp
2- veno costriction casuing increasing vr decreasing vennous capacitenss of blood
3 -decrrease in capillary pressure casuing isf shift to capillarires increasing its preussre thus BP intermdeiate regulation
ALL THIS IS RESERVED IN FALL OF ABP
vmc has direct effect on the heart
+chrono ino tropics incresaing ABP
What is the acute systemic nervous regulation of the blood flow ?
VC : sympathtaic NE fibers from VMC casuing VC of vessels lowering the blood flow to organs
VD : Inhibition of the VMC mentioned above !
the sympathtaic cholinergic fibers from the hypothalamus causing release ach causing VD Of blood vessles .
ecercise fear high bb baro carotid sinus syndrome
Sympathatic beta adrenergic affecting b2 receptor vd of skeletal and liver bv
the parasympathahtc cholinergic system casuing Vd
Antidromic vasodilator fibers injured skin is affected casuing stimulatoon fo afferent nerve fibers casuing vd of the bloods vessel ! ! ده الي بيحصل في الالتهاب؟ ؟
Antidromic vasodilator fibers fucntion ?
injured skin is affected casuing stimulatoon fo afferent nerve fibers casuing vd of the bloods vessel ! ! ده الي بيحصل في الالتهاب؟ ؟
the vascoconstrictor humoral mechanism of regulating the blood flow are ? مهم جدا
1- Angiotensin 2 thee most potent vasoconstrivcto? Noreadrenaline on a receptora adrenaline high dose ADH high dose Serotoin TXA2 ENDOTHELIN 1 Ca of musclear vessels constriciton أنس قاطن ANAS CaTEN angiotensis adrenaline nor adrnaline adh serotoinnin txa2 ca endotelin
TIP TXA2 ANATAGOINZES PGE2
The vasodilator systemic humoral regulation of the blood flow ? مهم جدا
the adrenalis in low dose b take the upper hand ANP bradykinin k mg h citrate co2 no PGE2
acute Local regulation of blood flow
Auto regulation
ACTIVE HYPERMIA
REACTIVE HYEPRMIA
Autoregulation method ?
intiricsic in vascular smooth muslce withou nervous or houmoral mechanisms
autoregulation mean that the blood flow remian constans in a wide range of abp 60- 160 mm Hg
mention organs of higest and lowest autoregulation ?
highest : the brain the heart
lowest : skeletam muscles and skin under neurogeinc stimuli
show the concept of autoreguation ?
If perfusion pressure to the heart is lowerded there will be autoregulatory vasodilating mechanism to iincreasit it bac k
if the opposite ! there will be vasoconstricting regulatory mechanism in smooth muscles of vessels to decrease blood flow to the heart !
show Myogenic theory
the increased pressure inside the vessel
causes its (stretch )
and increased flow
causing the myogenic effect of muscles of blood vessels to appear vasoconstircting the blood vessel returining the blood flow to normal !
Expain the metabolic theory
increasing tissue activity
increasing the CO2 K H LAVTIC ACID ADENOSIN
VASODILATION
INCREASING BLOOD FLOW !
TISSUE PRESSURE THERORY
arrival of more blood to capillary with high pressure casuing more filtration to isf causing more pressure around the capillaries by this fluid filtrated vascoctriviton capiillaries and the flow dec to normal
Expain active hypermia ?
it is similar to the metabolic theory of the autoregulation
when skeletal muscle work there is increase in tissue activity
and increasing co k h lactic acid and adenosine !
this will lead to vd of skeletal blood vessels
and increasing the blood flow washing out these metabolites
returning to vasconcstiction normalizeing the flow
TIP
WHEN TISSUE ACTIVITY INCREASES BLOOD FLOW TO IT MUST INCREAST TO MEET ITS DEMANDS !
THE ROLE OF ACE IN PREVENTING COUGH /
It decreases the formation of bradykinin from kininogen
Reactive hypermina illustrate !
the blood flow after a period of ( OCCLUSION )
THIS leads to increse co2 k h lactic acid adenosine
casuing vd of bloods vessel
and this is highest in
Heart brain
intermediate skeletal musclers
lowest skin LIVER LUNG
Chronic regulation of blood flow
DESCRIBE .
Long term regulation of the blood flow in case of partially occluded blood vessel
the occulded segment will relase 3 sub = vascular endotheliah growh factor ,platelet derviced endothelidal growth factor and angioenen
will form collaterals to increase o2 supply to tissue
epecially heart brain and kideny
least the skin skeletal muscles
Blood flow to brain heart kideny liver skin skeletal muscle
Brain 53 ml/min/100gm heart 84 ml/min /100gm kideny 420 ml/min/100mg skin 12 liver 57
heart and brain and kikdeny and liver
VMC TONE
AUTOREGULATION
THEY HAVE LOWEREST VMC TONE EXCEPT KIDENY IN Hge
THEY HAVE HIGHEST AUTOREGULATION
skeletal muscles blood flow ?
2.7 m;/mmin/100gm
high VM TONE
LOW AUTOREGULATORY MECHANISMS
TIPS
LIVER KIDENY DKLETEAL MUSCLES 2/3 BLOOD FLOW
TIPS
KIDENY LIVER HEART BRAIN HIGHEST BLOOD FLOW PER UNIT WEIGHT
LOW VM TONE AND VASCULAR RESISTANCE
TIPS
SKIN SKELETAL MUSCLES OTHER TISSUE BONE CARTILAGE CT
HAS LOWER BLOOD FLOW PER UNIT TIMNE DEUR TO HIGH VM TONE AND HIGH VASCULAR RESISTANCE
The kidenys are the clearance organ so the high blood flow reaching it is non nutirictional but shar in urine formation`
why in hge the kideny is conquered under the VMC
in attempt to decreasee blood floww to kideny by vasoconstriction of it blood vessel preventing urine frmation and keepin plasam volume !
