Chapter 19

Chapter 19

Blood

Blood Overview

WBC’s

RBC’s

liquid

cells(formed

elements)

spin blood

separate into 2 parts (3)

Blood

OverviewPlasmaFormed elements

RBC’sWBC’splatlets (fragments)

hemostasis

chapter outline:

Blood Overview

fluid CTpart of the cardiovascular system

(heart, vessels)

provide nutrients, O2, chemical messagesremoves wastesprovide protection

to/from/for all the cells of the body

Blood Overview

•transport:dissolved gasesnutrientshormoneswastes

•regulate:ionic composition and pH of body fluids

Blood Overview

•restrict fluid lose at injury

•stabilize body temperature

•defend against toxins and pathogens

Blood Overview

•restrict fluid lose at injury

•stabilize body temperature

•defend against toxins and pathogens

Blood Overview

plasma

~55% of blood

H2O 92%plasma proteins 7%ionsnutirentswasteshormones

Blood Overview

formed elements

produced through hemopoiesis

99.9% RBC’s0.1 % WBC’s and platlets

Blood Overview

whole blood

•38˚ C•5x more viscous than H2O

(sticky, thick)

•slightly alkalaipH 7.35 - 7.45

5-6 L in average adult male (165)4-5 L in average adult female (125)

(7% of body weight)

Clinical Note

blood donations

median cubital veinvenipuncture

easy to findthin walls than arterieslower bp than arteries

Clinical Note

capillary blood

finger tipearlobetoe / heel (infant)

small quantity (drops)

Clinical Note

arterial blood

radial or brachial artery

check blood gases

Stop here 3/21Lec #29

Blood plasma

body fluids

ICFECF

interstitial fluidblood plasma

Blood plasma

similar in composition to interstitial fluid (ECF) (different than ICF)

but different than ECF in:

dissolved gases (O2, CO2)(always being used by

cells)

dissolved proteins(don’t cross capillary

walls)

Blood plasma

7.6 g% (5x ICF)7.6 grams / 100 ml plasma

large size and globular shapeprevents them from leaving vessels

three classes of proteins:albuminsglobulinsfibrinogen

proteins:

Blood plasma

proteins:

albumins

60% of plasma proteinsmade in livertransport:

fatty acidshormonesother stuff

Blood plasma

proteins:

globulins35% of plasma proteinstwo typesimmunoglobulins

transport globulinsaka., antibodies (Ab)

hormone-binding (thyroid H)

metalloaproteins (iron)

apolipoproteins (lipids)

steroid-binding (testosterone)

Blood plasma

proteins:

fibrinogen4% of plasma proteinsblood clotting

converted to fibrin (strings)(framework for clot)

plasma without clotting stuff= serum

Blood plasma

proteins:

other plasma proteinsvarious

hormones

origins of proteinsliver makes 90%

plasma cells make antibodies (Ab)

100 keys pg. 643

“Your total blood volume, in liters, is roughly equal to 7% of your body weight (in kilograms). Approximately half the volume of whole blood consists of cells and cell products. Plasma resembles interstitial fluid, but it contains a unique mixture of proteins not found in other extracellular fluids.”

Clinical Note

Plasma expanders

used to increase blood volume

(buy time to determine blood type)

isotonic (normal) saline solutionsshort-lived diffuse into interstitial fluid and

cells

Ringer’s solution has lactate (slows diffusion)

Dextran in saline

Clinical Note

Plasma expanders

temporarily replace blood volume

don’t help increase O2 carried

need to give or make new RBC’s

Formed elements

RBC’saka., red blood cells

erythocytes

contain pigment molecule hemoglobin

Hb + O2 HbO2

(dark) (bright red)

RBC’s

Quantity

# RBC’s in one µl (microliter)(1 mm3)

about 5,000,000 cells / µlx 5 L of blood

25,000,000,000 RBC’s in adult

RBC’s

Quantity

percentage of whole blood occupied by RBC’s

hematocrit

average is about 45 males42 females

RBC’s

Quantity

What factors may affect the hematocrit ?

increase

decrease

dehydrationEPO stimulation

bleedingproblems with RBC production

RBC’s

Structure

unusual cellslack most organelles

(nucleus, mitochondria, etc)except cytoskeleton

biconcave discs

fig. 19-2c

fig. 19-2d

RBC’s

Structure

shape

large surface area to volume ratio

absorption and release of O2

form stacks to go through vessels

can bend and flex to get through narrow capillaries

RBC’s

Structure

lack of organelles

cannot dividecannot synthesize proteinscannot repair itself

short life-span (120 days)replace ~1% each day

low energy demands

RBC’s

Structure

What do they have inside ?

95% of proteins inside the cell is

hemoglobin (Hb)14 g%

RBC’s

Structure of Hemoglobin

complex structure4 polypeptide chains

2 alpha () chains2 beta () chains

(amino acids)

each chain has a hemepigment moleucleFe2+

fig. 19-3

RBC’s

Structure of Hemoglobin

280 million Hb molecules/RBC

one RBC can carry over a billion O2

O2 bound depends on [O2]if [CO2] is high

bind to Hbcarbaminohemoglobin

RBC’s

Structure of Hemoglobin

low hematocritlow Hb

reduced O2-carrying capacity

= anemia many forms

reduced flow of O2 to tissues

weakness, lethargy, confusion

RBC’s

Formation / Turnover

exposed to severe mechanical stresscannot repair themselves

macrophagesengulf old/damaged cellsengulf cell parts after hemolysis

RBC’s

Formation / Turnover

hemolysis

releases Hb from cells

if phagocytosed - recycledif not, eliminated by kidney

hemoglobinuria

red or brown urinelots of Hb in urine

RBC’s

Formation / Turnover

hemolysis

hemoglobinuria

hematuria

intact RBC’s in urinemeans kidney damage or

blood vessel damage

RBC’s

Formation / Turnover

recycling (by macrophages)

globin proteinsamino acids

reused

RBC’s

Formation / Turnover

recycling (by macrophages)

heme (without Fe2+)

bilverdin (greenish) (bruise)

bilirubin (yellowish)(jaundice)

excretion (urine, feces)

RBC’s

Formation / Turnover

recycling

Fe2+ (if free, is toxic to cells)

transported to bone marrowby transferrin

used to make new RBC’sneed 26 mg/day

1-2 mg is usually enoughmost is recycled

RBC’s

Formation / Turnover

recycling

too little Fe2+

reduction of RBC production

dietary deficiencyiron absorption

iron-deficiency anemia

RBC’s

Formation / Turnover

recycling

too much Fe2+

excessive buildup in heartlinked to heart disease

excessive buildup in liver

fig. 19-4

to here 3/23lec # 30

100 Keys (pg. 649)

“Red blood cells (RBC’s) are the most numerous cells in the body. They remain in circulation for approximately 4 months before being recycled; several million are produced each second. The hemoglobin inside RBCs transports oxygen from the lungs to the peripheral tissues; it also carries carbon dioxide from the tissues to the lungs.”

RBC’s

Production

embryo yolk sacfetus liver, spleenadults red bone marrow

(aka., myeloid tissue)

erythropoiesis

RBC’s

Production

hemocytoblast myeloid stem cell proerythroblasts - - - normoblasts (sheds nucleus)

reticulocyte (enter blood)

mature RBC

RBC’s

Production

fig. 19-5

RBC’s

Regulation of Production

requirements:

amino acidsironvitamins

B6

folic acidB12 meat/dairy products

absorption requiresintrinsic factor

RBC’s

Regulation of Production

requirements:

B12

if not enough eatenor absorbed

pernicious anemia

RBC’s

Regulation of Production

stimulated by EPOerytropoietinerythropoiesis stimulating

hor.

made by peripheral tissues especially kidney when exposed to low oxygen levels

hypoxia

RBC’s

Regulation of Production

what might trigger kidneyto release EPO?

anemiareduced blood flow to kidneylow O2 in lungs

(disease or high altitude)lung damage

RBC’s

Regulation of Production

effects of EPO

stimulates cell division inerythroblasts and stem

cells

stimulates Hb synthesis and maturation of RBC’s

RBC’s

Regulation of Production

effects of EPO

RBC production canincrease from

3,000,000 cells/second to

30,000,000 cells/second

RBC’s

Regulation of Production

effects of EPO

important following blood loss

given to healthy person(Olympic endurance athletes)blood can carry more O2

but, hematocrit rises (65+)blood get thickerstrain on heart

RBC’s

Regulation of Production

effects of EPO

same applies to blood doping

RBC’s

Blood testing

table 19-1

table 19-1

100 Keys (pg. 649)

“Red blood cells (RBC’s) are the most numerous cells in the body. They remain in circulation for approximately 4 months before being recycled; several million are produced each second. The hemoglobin inside RBCs transports oxygen from the lungs to the peripheral tissues; it also carries carbon dioxide from the tissues to the lungs.”

Blood typing

antigens“foreign” moleculescan trigger immune response

cells (including RBC’s) haveproteins on their surface

your immune system “ignores” the molecules on the surface of your cells because they are “self”

Blood typing

your body makes antibodies (Ab)(aka., immunoglobulins)

to attack and destroy antigens

There are three (of 50) important “antigens” used for blood typing

ABRh

Blood typing

if your cells normally have A on surface

(A is “self”)

your immune system will ignore it, but has antibodies to attack B

(anti-B antibodies)

You have type A blood

Blood typing

if your cells normally have B on surface

(B is “self”)

your immune system will ignore it, but has antibodies to attack A

(anti-A antibodies)

You have type B blood

Blood typing

if your cells have A & B on surface(both are “self”)

your immune system will ignore them

You have type AB blood

Blood typing

if your cells have neither on surface(neither are “self”)(both are foreign)

your immune system has antibodies to attack both

You have type O blood

fig. 19-6

agglutination

hemolysis

Genetics of blood groupings:

ABO system

three alleles

IA

IB

i

IA IA

IA iIB IB

IB iIA IB

i i

AABBABO

DOMINANTrecessive

Other blood groupings:

ABO system

Rh system

C, D, E: close on same chromosome

Dominant/recessive

C, D, or E Rh positive

ccddee Rh negative

Blood typing

if your cells have Rh factor on surface(Rh is “self”)

your immune system will ignore it

You have type Rh+ (positive) blood

Blood typing

if your cells lack Rh factor on surface(Rh is “foreign”)

your immune system will make antibodies to attack it

You have type Rh- (negative) blood

table 19-2

Blood typing

cross reaction

Ab + RBC agglutinationand hemolysis

blood transfusiontest for

compatability

Blood typing

standard test

determine donor’s and recipient’s blood type using ABO and Rh systems

mix drops of blood withanti-Aanti-Banti-Rh

fig. 19-7

A+

B+

AB+

O-

universaldonor

fig. 19-7

Blood typing

standard test

just tested 3 of 50+ possible antigens

if time and facilities allow:cross-match testing

mix donor and recipient bloodand look for problems

Blood typing

HDN

Hemolytic disease of the newborn

Blood typing

HDN