Temperature change muscle contraction

[sozme]

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What effect does temperature change have on muscle contraction?

 

[Temperature101]

What effect does temperature change have on muscle contraction?

I dont know from what angle this question is coming from, but I assume that an increase in temperature would generate more muscle contraction because blood vessels leading to the muscle will dilate, thereby, muscle receiving more blood (ie oxygen). A decrease in temp would be the opposite. The heart can be a perfect example of what I just said.

 

[SaintJude]

Yeah, I think it will help if you explain the context of the question.

 

[sozme]

I dont know from what angle this question is coming from, but I assume that an increase in temperature would generate more muscle contraction because blood vessels leading to the muscle will dilate, thereby, muscle receiving more blood (ie oxygen). A decrease in temp would be the opposite. The heart can be a perfect example of what I just said.

Yeah, I think it will help if you explain the context of the question.

In relation to actin, myosin, calcium, ATP availability....

 

[ljc]

In relation to actin, myosin, calcium, ATP availability....

That's still not a question. Give us the question/section that prompted you to post this.

 

[MedPR]

What effect does temperature change have on muscle contraction?

Depends what exactly you are asking.

If you are outside in cold weather, your body will shunt blood to your internal organs, thus shunting blood away from your periphery and skeletal muscles. You will be less able to move freely. This should be intuitive if you've ever been out in the cold.

 

[Class1P]

Could be a prompt for asking about protein binding kinetics or enzyme effeciency. In that case there is an optimal temp and pH at around 37C and 7.2 respectively.

 

[cbrons]

.Temperatures effects muscle contraction in an indirect manner. The strength with which oxygen binds to hemoglobin is effected by temperature and pH, among other factors. At lower temperatures, hemoglobin has a higher affinity for oxygen (shifting the oxy-hemoglobin dissociation curve leftward). This decreases the partial pressure of oxygen in the tissues, and results in less ATP production. During exercise, muscles also have a higher metabolic rate, and consequently require more oxygen. This results in the production of carbon dioxide and lactic acid, raising temperature and decreasing pH (pH changes are known as the Bohr effect). Both of these measures reduce hemoglobin’s affinity for oxygen and shift the oxy-hemoglobin dissociation curve rightward, facilitating an increased rate of perfusion..

..
.Not sure if this is MCAT-required knowledge though.
.

 

[MT Headed]

Knowing what causes a dissociation curve to shift left or right is mcat worthy.

In biochemistry we realized the the things that caused a rightward shift and the hemoglobin to dump off oxygen were:
2,3-BPG
CO2
Heat and H+ ions (acidic)

...and 'BCH' was our school's abbreviation for BioCHemistry. Kind of silly, but I still remember it.

 

[MedPR]

Knowing what causes a dissociation curve to shift left or right is mcat worthy.

In biochemistry we realized the the things that caused a rightward shift and the hemoglobin to dump off oxygen were:
2- BPG
CO2
Heat and H+ ions (acidic)

...and 'BCH' was our school's abbreviation for BioCHemistry. Kind of silly, but I still remember it.

Why does 2-bpg cause a shift?

 

[MT Headed]

Why does 2-bpg cause a shift?

Ugh, my bad. I meant to say 2,3-BPG. Which makes more sense via the nomenlclature... the "bis" in bis-phospho glycerate means there are two phosphates, not one.

Anyway, philosophically 2,3-BPG is a side product of glycolysis. So if there is a lot of it around (much like if there is a lot of H+ (lactic acid), CO2, and heat) it implies that the cell is working hard and could probably use some extra oxygen.

Biochemically, it sticks to hemoglobin in the "empty" ("T") state, causing it to both dump oxygen and not pick up any extra oxygen.

*guess I don't remember this stuff as well as I thought. blush*

 

[MedPR]

Ugh, my bad. I meant to say 2,3-BPG. Which makes more sense via the nomenlclature... the "bis" in bis-phospho glycerate means there are two phosphates, not one.

Anyway, philosophically 2,3-BPG is a side product of glycolysis. So if there is a lot of it around (much like if there is a lot of H+ (lactic acid), CO2, and heat) it implies that the cell is working hard and could probably use some extra oxygen.

Biochemically, it sticks to hemoglobin in the "empty" ("T") state, causing it to both dump oxygen and not pick up any extra oxygen.

*guess I don't remember this stuff as well as I thought. blush*

So theoretically an increase in any intermediate product of glycolysis would cause a shift?

 

[MT Headed]

So theoretically an increase in any intermediate product of glycolysis would cause a shift?

I wouldn't go that far. I suppose a buildup of things downstream of 2,3-BPG would eventually cause the system to plug up and build 2,3-BPG also, but that's indirect. And a buildup of precursors wouldn't affect things.

The effect of 2,3-BPG is pretty direct. It's like a monkey wrench that sticks into hemoglobin itself and gums up the works so that the heme dumps its load of oxygen, as if it forces a dump truck into the lifted position.

 

[superman3]

I dont know from what angle this question is coming from, but I assume that an increase in temperature would generate more muscle contraction because blood vessels leading to the muscle will dilate, thereby, muscle receiving more blood (ie oxygen). A decrease in temp would be the opposite. The heart can be a perfect example of what I just said.

Admittedly, the question needs to be more specific, but I think the above is false. Rather, when there is a decrease in temperature, muscle contraction, specifically, skeletal muscle contraction increases in order to generate heat...a.k.a. shivering.

 

[theseeker4]

Admittedly, the question needs to be more specific, but I think the above is false. Rather, when there is a decrease in temperature, muscle contraction, specifically, skeletal muscle contraction increases in order to generate heat...a.k.a. shivering.

But that is a nervous system-prompted reaction, not a direct reaction by the muscle, correct?

 

[MT Headed]

Admittedly, the question needs to be more specific,

Yeah that about sums up this thread.