Can dreams be memorised? Would it be possible to activate the human memory and "access" it by means of encouraging certain hormones, to assist a sleeping body to memorize dreams and later (meaning minutes, days, months or even years) access it again with the same hormones - something like a trained body function. 

This could perhaps help in solving certain criminal cases or assist in psychological healing (for schizophrenia and the likes). I'm just curious about the possibilities and have absolutely no knowledge of how the brain works. This was just a wild idea that came to mind and I was wondering about the possibilities.
I don't know how it is when it goes about hormones but for sure dreams can be remembered and this remembering of dreams can be improved.

One of the most popular methods is trying to think about somebody's dreams just after waking up. It is also important to tell it loudly, record it or write it down.
After some time (even few days) of writing down your dreams a person is able to remember not one, but two, three or more dreams from one night.

The case of getting access to your previous dreams lately is connected with lucid dreaming - if you are able to have lucid dreams whenever you want, you also can initiate these situations which you like. But it is much less scientifically described case.