in the quote "you, help me" why do i have to use を and not が
IE: あなたは、私を助けて！instead of あなたは、私がたすけて！
Why 私 is a direct object? I thought that only objects and nouns could be a direct object, so I assume I was wrong?
Could someone, please, bring some light on this?
Edit: I have some knowledge in the transitive and intransitive verbs, but I have never used examples where 私 is the direct object, is this matter related to the transitive/intransitive verb or not?
Thanks in advance :)