Red potions (Roter trank) - How to change it's function?

[ElectriX3]

Hello, I was wondering if anybody knows, where to change "function" of these potions? I mean specifically:

1) The time between recharging of HP,
2) The amount of HP recharged by each "step".

I know you can change the regenerated amount of HP in item_proto, but where is that "heart" script, which makes these potions work the way they do? Or at least, where should I look for it?

- Yes, I have decompiled & extracted client.
- Yes, I have decompiled server-side software, but no luck finding it there.
- No, I don't mean the automatic HP regeneration.

Thank you very much in advance .