Homeostasis roughly means 'unchanging state'.
Homeostasis is the state of equilibrium which the body strives to maintain through a complex system of regulatory feedback mechanisms. For example: if you get too cold, you start shivering (the movement of the muscles generates heat); if you get too hot, your body perspires (it is cooled as the sweat evaporates). Here's a good formal definition:
http://medical-dictionary.thefreedictionary.com/Homeostasis (Biology)
If a body has been working in a certain fashion for some time - and not necessarily in a healthy fashion - it will regard certain states as 'normal' and strive to maintain those states.
When treating with insulin you are in a way doing battle with the body's homeostatic mechanisms for controlling blood glucose concentration. In very simplistic terms, regulation is a gradual process because the body needs to re-adapt to using insulin properly again (i.e. overcome insulin resistance) and also to become reaccustomed to operating in the healthy normal blood glucose range (i.e. the body needs to learn that 'healthy normal' is not life-threatening). Once this is achieved the body will then work to maintain blood glucose levels at or around this new, lower 'setpoint'. If the pancreas beta cells can recover enough function the cat may not need injected insulin and thus go into remission, otherwise the cat should (in theory) be able to run in a relatively narrow BG range (well-regulated; less swingy/bouncy) with support from injected insulin.
Mogs
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