Endocrine PhysioEx Metabolism Lab Assignment

What was the effect of propylthiouracil (PTU) injections on the normal rat's BMR? Why did this rat develop a palpable goiter?

It slowed the metabolic rate, compared to normal baseline. PTU inhibits production of thyroxine...that's why this rat developed palpable goiter.

What was the effect of thyroxine injections on the normal rat's BMR?

It would suffer from Hyperthyroidism because it would have too much thyroxine in its blood.

If an animal has been hypophysectomized, what effect would you expect to see in the hormone levels in its body?

TSH levels will be missing because the pituitary gland is removed, so it would have a decreased metabolic rate.

What was the effect of thyroxine injections on the hypophysectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Was the dose of thyroxine in the syringe too large, too small, or, just right?

The Hypophysectomized rats also had high BMR after injections making the rat hyperthyroid. The BMR was a little higher in the rat with no pituitary gland with thyroxine than that of the normal rat. The thyroxine in the syringe was too small of a dose.

What was the effect of TSH injections on the thyroidectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Why was this effect observed?

The TSH had no effect on this rats BMR.

1 What was the effect of thyroid-stimulating hormone (TSH) injections on the normal rat's BMR?

The TSH injections increased the BMR of the normal rat and caused Goiter.

What was the effect of PTU injections on the hypophysectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Why was this effect observed?

The effect of PTU injections on the hypophysectomized rat's BMR was not visible because the rat is missing the pituitary gland.

What was the effect of TSH injections on the hypophysectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Was the dose of TSH in the syringe too large, too small, or, just right?

The metabolic rate was increased to 1,839.80 which was higher than the normal rat's BMR. It has a pituitary gland, so some hormones are still there.

Why did the metabolic rates differ between the normal rat and the surgically altered rats? How well did the results compare with your prediction?

The metabolic rates differed between the normal rat and the surgically altered rats because the surgically altered rats could not produce specific hormones (t4 and TSH) since they no longer have either a thyroid or pituitary gland.

What was the effect of thyroxine injections on the thyroidectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Was the dose of thyroxine in the syringe too large, too small, or, just right?

The thyroidectomized rat had a high BMR after the injections, making the rat hyperthyroid. Before injections the rat was hypothyroid. The dose was too low.

What was the effect of PTU injections on the thyroidectomized rat's BMR? How does the BMR in this case compare with the normal rat's BMR? Why was this effect observed?

This rat had a slowed metabolic rate because it didn't have a thyroid and wasn't as affected by the injections.

If an animal has been thyroidectomized, what hormone(s) would be missing in its blood?

it would be missing Thyroxine in its blood, also known as t4, since thyroid gland is removed.

Which rat had the fastest basal metabolic rate (BMR)?

the normal rat with thyroxine