The Endocrine System, Hormone Interactions

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Hormones act together, facilitate one another or against each other.

In synergism, the Effect if Interacting hormones is more than additive
Glugagon, Cortisol and Epinephrine increase the blood glucose levels -
Their combined effect is more than additive, the epinepharine potentiates the glucogon's effect on blood glucose, 
Augmentin is an example of synergism


A permissive hormone allows another hormone to exert its full effect
Permissiveness, if thyroid is not present the maturation of the reproductive system is delayed. Tyroid cannot by itself stimulate sexual maturation of the reproductive system, tyroid hormone is considered permissive.


Anatgonistic hormones have opposing effects
Competitive inhibition or antagonists
Glucagon and Growth Hormone, both release glucose are antagonists to Insulin. Growth hormone decreases  the number of insulin receptor,  providing functional antagonism to insulin.

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