Brief Answer:
Cortisol prepares person to tackle situations.

Detailed Answer:
Hello,

Thanks for writing to us.

You have mixed up all information in your mind and seems to be confused.

Cortisol from adrenal gland prepare the person to tackle the adverse situation either it is external or internal.

When person perceives fear, hypothalamus gets signals from parts of brain and pituitary-adrenal axis becomes activated and cortisol secretion is started.

Cortisol acts in central and peripheral system to increase blood supply, to fasten the metabolism to provide more glucose to generate strength as well as activate motor part of brain to function fast.

These all factors lead to help the person with fighting the situation or to make him/herself away from the situation.
E.g. if street dogs comes near to us suddenly and starts barking, we either fight with it by throwing away something towards it/ shout loudly against it(fight response)( or we may run away from that situation(flight response).

Anger is also response/emotion to some uncomfortable situation either external or internal. Same thing happens and hypothalmo-pituitary-adrenal axis becomes activated as described above when person is in anger but with somewhat lesser potential than that in case of fearful situation.

So in both cases cortisol is going to increase.

You mentioned, "My question is also about inflammation because I have seen that if the fear is perceived to be external then inflammatory response is reduced but if the fear is perceived to be internal then the inflammatory response may be increased. And in both cases fear would mean increased cortisol".

I am not getting the point, please give some example of external and internal fear. However still I would comment.
No it is not like that at all. In both the case cortisol will be there fear is external or internal and inflammation will be reduced. Inflammation process is not related to cortisol but it is related to infection and injury. Depending upon severity of inflammation inducing agent severity of inflammation process(it is chain of reaction induced by different types of white blood cells) varies. Cortisol just works to control over inflammation to prevent damage to normal tissues.

Anger can fasten wound healing but not so much. Anger means cortisol which means increase blood supply and glucose to peripheral tissue(wounds) which helps in wound healing. Cortisol activity of suppressing immune system and inflammatory response at wound is balanced by body automatically. There is not so much cortisol that it suppresses the immune system as I mentioned previously. Body has internal system controlled by hypothalamus and feedback chain to control appropriate amount of hormone secretion.

When stress is severe and persistent like for weeks or months, excessive cortisol secretion is there due to dysregulation of hypothalmo-pituitary-adrenal axis. In that case immune system suffers.

I hope you are clear now. If still any query is there I will be glad to answer. If you still need more reading, provide me your education background so I can search and send link accordingly as this topic contains books on it!

Regards,

Dr.Chintan Solanki.

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