>
> Joel wrote:

>> August Pamplona hotmail.com> wrote:

>>>Phil Stovell wrote:
>>>

>>>> Prof Hurd's experiments show that, after training to self administer
>>>> heroin by pushing a lever, rats exposed to THC took more heroin as adults
>>>> than those not given the chemical. They were more sensitive to lower
>>>> concentrations of heroin than unexposed rats and took more in response to
>>>> stress.

>>>
>>> Yes, of course, since they are sensitive to lower
>>>concentrations they are forced to self-administer more of it to get the
>>>same effect.*
>>>
>>>* Yes, that was sarcasm.

>>
>>
>> That part makes sense to me, actually. It reflects the fact that many
>> people experiment (including because of some medical pain-relief
>> episode) with opiates, but never progress into addiction. The ones
>> that start out more sensitive to lower concentrations of heroin are
>> probably experiencing a conditioned reward; activating the addiction
>> disease. Later, they will be more driven to use, ultimately in larger
>> amounts, and become the rat equivalent of hardcore addicts.

>
> Not to cheekily butt in here, but what kind of rats were these?