Acid - Base Balance

Acid

molecule that can liberate hydrogen ions

Base

molecule capable of combining with hydrogen ion

what is a strong base

bicarbonate

what is normal pH

7.35-7.45

What is acidosis

pH < 7.4

What is alkalosis

pH > 7.4

What 2 things increase concentration of H+

Accumulation of acids and loss of bases

increase concentration of hydrogen ion =

pH drops

how does long term starvation lead to metabolic acidosis

results in increased fat metabolism and diabetic ketoacids

how does uncontrolled diabetes lead to metabolic acidosis

results in high rates of fat metabolism and diabetic ketoacidosis

what are some causes of metabolic alkalosis

loss of acids from the body

severe vomiting

kidney disease

what are the 3 primary sources of hydrogen ion in contracting skeletal muscle

carbonic acid (aerobic metabolism)

lactate (anaerobic metabolism of glucose)

ATP breakdown and releasing hydrogen ion

Where does carbonic acid come from

Aerobic metabolism of glucose

Where does lactate come from

Anaerobic metabolism of glucose

In many sports, what is the risk of acid-base balance related to?

directly related to the efforts of the competitor

in regards to acid-base balance, what can you increase to improve performance

increase blood buffering capacity

____ intensity exercise results in production of LA and increased H+ in muscle fibers and blood

High

how does increase hydrogen ions impair performance

- inhibits glycolytic and citric acid cycle enzyme activity

- can impair muscle contraction by competing with Ca in binding to troponin

what are intracellular buffers

classes of cytosol of muscle

bicarbonate (converts strong H to weak H)

phosphate groups (converts strong H to weak H)

cellular proteins (accepts H ions)

histidine-dipeptides (accepts H ions)

what are extracellular buffers

bicarbonate

hemoglobin

blood proteins

_____ and _____ convert strong acid into weak acid

Bicarbonate, phosphates

____ and ____ accept hydrogens

Proteins, histidine-dipeptides

what intracellular systems are the two primary transporters of H out of cell

sodium-hydrogen exchanger

monocarboxylate transporter

what is the role of ingestion of sodium buffers in performance

studies shown sodium bicarbonate and sodium citrate can increase time to exhaustion during high-intensity exercise (80-120% VO2 max)

which muscle fibers have greater intracellular buffering capacity

type 2

what is the most important of the 3 extracellular buffering systems

bicarbonate system

When ____ decreases, hydrogen increases causing the reaction to move to the ___

pH, left

when do the kidneys play a role in acid-base balance

they play a role in long term acid-base balance...not during exercise

how do kidneys regulate blood pH

by regulating concentration of bicarbonate in blood

during exercise, the amount of hydrogen ion production depends on

exercise intensity

amount of muscle mass involved

duration of exercise

____ and ____ pH declines with increasing intensity of exercise

Blood, muscle

why is muscle pH lower than blood pH during exercise

it is the site of H production and has lower buffering capacity

what does majority of H ion buffering in the muscle

intracellular proteins (60%) ~ first line of defense

respiratory acidosis

A drop in blood pH due to hypoventilation (too little breathing) and a resulting accumulation of Co2... increasing H ions

_____ ____ causes lethargy, confusion, altered mental status, and cyanosis

Respiratory acidosis

respiratory alkalosis

Arise in blood pH due to hyperventilation (excessive breathing) and a resulting decrease in CO2... decreasing H ions

_____ ____ causes tachypnea, tachycardia, hyperventilation, and dizziness

Respiratory alkalosis

Respiratory ____ is elevated arterial blood pH with low PaCO2

Alkalosis

Respiratory ___ is low arterial blood pH and elevated PaCO2

Acidosis

Metabolic ___ is elevated arterial blood pH and elevated PaCO2

Alkalosis

Metabolic ____ is low arterial blood pH and low PaCO2

Acidosis

Respiratory is ____ pH and PaCO2

Opposite

Metabolic is ___ pH and PaCO2

Equal