Temperature Regulation

Question 1

Center for THERMOREGULATION

Answer 1

Hypothalamus

Question 2

Detected temp < Set Point temp

Answer 2

initiate HEAT GENERATING MECHANISMS

shivering - MOST POTENT
thyroid hormone production
decreased sweating
piloerection
skin vasoconstriction (a1)
brown fat in babies (B3)

Question 3

Detected temp > Set Point temp

Answer 3

initiate HEAT LOSS MECHANISMS

radiation - MOST POTENT
convection
sweating via evaporation
decreased heat production

Question 4

For heat LOSS

Answer 4

ANTERIOR hypothalamus

Question 5

For heat GAIN

Answer 5

POSTERIOR hypothalamus

Question 6

MOA OF FEVER

Answer 6

PYROGENS –> INCREASED IL-1 (alpha and beta) and IL-6 –> INCREASED PGE2 –> INCREASED SET POINT temperature in hypothalamus –> HEAT GENERATING MECHANISMS

Question 7

Inhibits COX –> decreased PGE2 –> decreased set point temp

Answer 7

ASPIRIN

Question 8

Inhibits release of arachidonic acid from brain phospholipids –> decreased PGE2 –> decreased set point temp

Answer 8

STEROIDS

Question 9

Increases set point temperature

Answer 9

PGE2

Question 10

Overexcitation of skeletal muscles d.t. defective ryanodine receptors –> excess calcium release from SR

Answer 10

MALIGNANT HYPERTHERMIA

TRIGGERS:
Halothane
Succinylcholine
Heat stress
Vigorous exercise

TREATMENT:
Dantrolene