citations - How do I give credit to some image I included in my paper?

I recreated an image from a paper I liked (didn't use the same image to get out of the asking permission which could take a while). Now the reviewer asked us to give credit to the original paper. How do I do that? Is it okay to write that my image was 'inspired' from this other paper, as I didn't copy the image but used the image as a reference to create my own?

Its a drawing of blood vessels (with appropriate details related to our work).

Answer

First of all,

permission which could take a while

Is not entirely correct. Most major publishers have an automated "permission request" system that in many cases automatically grants you permission to reuse a figure from a published paper. It takes about 5 minutes and usually you can find it in the journal's home page.

Now the reviewer asked us to give credit to the original paper. How do I do that?

This isn't too hard. One way, for instance, would be to add to the figure caption: "Redrawn after Smith et al. (2005)". I think it also depends on what the figure is about. Is it a graph with data points that you used? Is it some schematic drawing? If you edit your question to better describe the figure we can give you a better answer.