Memory and Patience

This week I have finally been let loose in the lab, or more likely, left alone to do the migraine experiments all by myself. After watching other researchers so effortlessly do this work in the last months, I now struggle to have a "successful" experiment, which can only occur with skill, patience, a cooperative rat, and a large amount of luck.

To have a successful experiment means many things - but first and most importantly, the rat has to fall asleep easily, without the need to give him additional shots of anesthesia, which can come back to screw things up later in the experiment, when the extra drug kicks in and the rat stops breathing. All of us in the lab have been having a rough time this summer with the rats in general. They are not falling asleep with the usual amounts of drug, and they are super stressed out.

I therefore came in super early one day, theorizing that since Melissa is the first one in and has better luck with getting her rats asleep, I may have the same luck by being the first one in the rat room. Great theory right? So there I am all by myself, thinking the rats will be relaxed since they haven't had any human contact in 12 hours, and I reach into a cage to get out a rat and put him in the weigh boat. Well, he was having none of that. He must have known what was coming (a shot), because he busted right out of the boat, pushing the lid off, and scampered across the counter. I chased down his tail, picked him up and put him back in the cage to calm him down for 10 minutes. It's a good thing he didn't launch himself right out the door, otherwise I would have been chasing him down the hallway.

I came back and tried again, this time holding the weigh boat lid on tight. I got his weight, measured out the drug, and reached in to grab him by the tail, and give him a shot in the abdomen (like I have been doing every day on a different rat since June). The rat freaked out, and bit me! I put him back in his cage, and decided that he won. He would not be used that day for my experiment, or any other day for that matter, since now he had a memory of what happens when the big bad humans reach into his cage.

So if I am lucky enough to get a rat that falls asleep easily, I then move on to more challenges on the path to a successful experiment. I have about 90 minutes to then perform all the surgical procedures, before the rat wakes up and starts complaining about what I am doing. It starts with having to place a catheter into the jugular vein (in the neck), which is easy now that I have had lots of practice. In the beginning it was astonishing to see a small hollow tube pushed into a tiny tiny vein that looks just like a very small piece of string to the naked eye, but under the microscope, looks like an elastic hollow tube, one that I have to carefully cut a small nick into with a scalpel, and then guide in the catheter.

You'd think that once the catheter is in, nothing more can go wrong with this apparatus. No such luck. Last week, just as we were ready to give the rat his migraine, we noticed that his breathing had increased, and he was getting light (meaning that the anesthesia was wearing off). The initial shot had worn off, and now we had to adjust the continuous drug, which is being supplied to his circulatory system via the catheter we put in his jugular vein (you know, just like in the hospital when they have to administer drugs intravenously). So we give him a bolus, or a few second injection of drug, in an attempt to bring him back down to the appropriate level of anesthesia. Nothing. He's still breathing hard and pulling his tail out of the way when we pinch it (one way to check his level of anesthesia). We bolus him again. Nothing. We bolus him again. Nothing. We have given him enough drug to kill him, and so we know that he is not getting it for some reason. We look to make sure that the line is not leaking. Looks good. We think that maybe the catheter is pushed up against some internal resistance, so we gently pull the catheter out a bit, and darn, the whole catheter falls out.

You might be thinking, well just put it back in right? Not so easily done. The rat by this time is all hooked up with the laser Doppler (to measure cerebral blood flow), the migraine drug injector, and two different electrodes that are recording different cells in the brain. No way to unhook everything, take the rat out of the set-up, and redo it all over again. So experiment over. And because these experiments take three hours to complete, once everything is all set up (which can take another 3 hours), there isn't even enough time to start another experiment the same day, unless I want to start working residency hours. (not ready for that yet)

After the catheter is successfully placed, I then have to do the hardest part of the whole experiment (for the faint of heart you might want to skip this paragraph). I have to put the rat in his ear bars. These are metal sticks that fit into his ear drums, and hold his head firmly in place so that the brain does not move during the experiment. Now, even though the rat is sleeping, there is nothing fun about picking up the rat's head, centering his right ear canal over a sharp pokey stick, and pushing at just the right angle, and with the perfect amount of pressure, to hear the small "pop" sound of the ear drum breaking. Then, while holding the head against the first bar, (so that it doesn't fall out and you have to find the ear canal again but without the aid of the "pop" sound), I then have to position the second ear bar into the left ear canal, again pushing with the right pressure and at exactly the right angle, to hear the second "pop."

I have successfully done this part of the experiment, um, maybe twice? Most of the time I have had to ask for help, since it seems like it's a "feeling" thing. No matter how much I am told how to do it, it's something that comes with practice, and I think I have finally gotten the "feel" of when I have done it right. I won't say much about when I have done it wrong, except for the one time that I pushed way too hard, and heard a very loud '"pop" that wasn't the ear drum, but a bone breaking. I felt terrible, and went into the other room to tell the other researchers that I had killed a rat while trying to put him in the ear bar, to which one of them replied (with a devious smile on her face) "murderer."

I had to laugh at the judgement, either that, or cry, because it is one of only many ways that the rat's life comes to an end in the lab. I still talk to the rats, and thank them, and still feel bad that this has to be done in order to make discoveries that one day will help humans end their own suffering. The only way I can continue to do this every day, is by a tremendous amount of patience, forgiveness for myself, and as a research here believes, a terrible memory. (You know, kind of like having children, you forget how much labor hurts so that you can do it again and again and again). I won't forget though. I'll remember each one of these little guys, and all that they are gifting to me this summer.