In regards to hypothermia, what is the mechanism of action involved after the body stops shivering . . . ?

after the body stops shivering in response to hypothermic state? For example, core temp drops a little, body responds with integrator and sensory response, but after a certain temperature the body no longer responds by shivering. I know the mechanism of hypothermia, please be as constructive in regards to the question.

It is believed that when the body reaches the state of shivering there are a number of various mechanisms in place. The Hypothalamus is the major regulator of temperature. It has a region in the preoptic area where reticular formation fibers sense sensory afferent information regarding the skin and integrates it into a higher center. The response is three things: Neurohormonal, involuntary sypathetic response, and semi-voluntary and voluntary beharioral responses.

Sympathetic Centers results in several responses including 1) Norepinephrine release from sympathetic fibers constricts skin vessels. 2) Brown fat (found in infants and some animals) oxidation increases causing thermogenesis. 3) Piloerection, occurs which traps air close to skin. 4) Epinephrine secretion from adrenal medulla increases thermogenesis. A Shivering Center in the hypothalamus is also activated which activates the Brainstem Motor Centers to initiate involuntary contraction of skeletal muscles causing shivering, which generates heat. Cold also activates some compensatory behavioral responses including huddling, voluntary physical activity (hand rubbing, pacing), sheltering next to a heat source and wearing warm clothing. Voluntary or semivoluntary behaviors in response to cold are activated by the higher brain centers, mainly the cortex and limbic system. When the environmental temperature decreases gradually (ex. summer to fall), the hypothalamus releases Thyrotropin Releasing Hormone which activates the anterior pituitary gland to release Thyroid Stimulating Hormone (TSH). TSH induces the thyroid gland to liberate large amounts of thyroid hormone (T3 and T4) into the blood. Thyroid hormone increases metabolic rate, which increases the amount of body heat production. As the body gets warmer, the hypothalamic sensors detect the warmth and diminish the heat producing and heat loss prevention responses.

If untreated, the patient then may lapse into a state of being irrational and subsequently unconscious. I am sorry, that is all I have.

i believe the body will slow blood flow to the extremities
thus allowing the core to stay warm protecting vital organs