“My work consists primarily of brain research,” says Dr. Phillip Groves, neuroscientist at UCSD. “The animals that I use mostly are experimental rats, laboratory rats, although I’ve done a number of experiments on different animals like cats and mice.” Seated under the window in his small office on the fourth floor of the medical teaching facility, Dr. Groves, 53, speaks in low, deliberate tones. “My work is supported by the National Institute on Drug Abuse, and my grant, which was awarded in 1973, is concerned with the mechanisms and sites of action of amphetamine and related drugs of abuse. That is, how does amphetamine work in the brain? What neurons does it affect and how does it do that? How does it affect the internal circuitry of brain systems?”
To determine these things. Dr. Groves and his students perform two kinds of experiments on lab rats electrophysiological and anatomical. He explains the former. “The rats are kept in the vivarium downstairs. One animal is taken out of the cage and brought up in its rat pan. Then, we anesthetize it for a subsequent acute experiment on the animal. Usually this is done with a subcutaneous injection of pentobarbital, which is a very potent surgical anesthetic. Then the animal is placed in a stereotaxic frame, which is an instrument by which we are able to penetrate the brain with electrodes and locate the tip of the electrode in a selected place in three-dimensional space. You look in an atlas of the brain in advance to find out that the particular nucleus you’re interested in is, for example, four millimeters below the surface of the brain, a millimeter and a half left of center, and so forth. The stereotaxic is, of course, calibrated in millimeters, and you twist dials to lower the electrode into the brain. We use the microelectrodes to record the activity of the cell, and hopefully that gives us information about what the cell is doing when a particular kind of drug is injected into the animal. Frequently, we know the means by which the drug affects the chemistry of the brain by interpreting the changes in electrical activity.
“After the end of the experiment, after you’ve recorded the activity of that cell, you section the brain and verify where your electrode was located by finding where the hole is that the electrode made in the brain and locating where the tip of it was.
“The other kind of work I do is anatomical. More and more over the years I have drifted toward anatomical experimentation in which we are concerned with the shape of brain cells. In those experiments you profuse the rats through the heart with a needle. You cut the right atrium of the heart, and you stick the needle into the left ventricle so the saline you inject goes through the entire system and pushes all of the blood out.”
After the profusion, which kills the rat, formaldehyde is injected, “which causes the brain to become fixed, and the fixation process makes the brain cells rigid, so when you slice them up, you can put them on a [microscope] slide.”
Without the formaldehyde, “the tissue wouldn’t be well enough fixed to be manipulated, and you couldn’t study it. It would just be a soft blob,” Dr. Groves explains.
When I was 12, I shot a sparrow out of a tree with a slingshot, and I remember feeling terrible about killing the defenseless, unsuspecting bird. Dr. Groves says these feelings occur in the lab as well, though after 30-plus years, they don’t for him. “I have developed a very callous attitude toward experimental animals,” he admits. “When I started my career, I did things that you wouldn’t believe I did. I had to chop off the heads of living rats, for example. I put them on a wooden block like an executioner and stunned them with the blunt side of a meat cleaver right into their neck, and then I’d flip the cleaver over in the air and come down and chop off the head. But emotions do come into play. Many students object to going into biological science because it involves animal experimentation. I’ve had some students who started and then quit and secondarily they have reached the conclusion that it was not worth their while to be killing animals. In fact, I've reached that conclusion myself for certain animals. I will not do any experiments on primates, even though I have many friends who do."
Why not primates?
He pauses. “I believe that the brain is essentially a product of evolution, and evolution has created a very large brain in some animals and those tend to be the really smart animals. A chimpanzee’s brain, for example, is very much like a human's, surprisingly like a human's. I think that anything with a sizable brain is going to have a mind, and I don’t think it’s necessarily appropriate to kill something that has a mind."
Dr. Groves concedes that there is “no clear line” between a lab rat and a chimpanzee that justifies killing one and not the other. I draw a line between primates and other experimental animals," he explains. “It’s a personal, subjective line.”
Working with lab rats involves some risks. First of all, they bite. Dr. Groves has been bitten “a number of times” in his career. Also, rats can carry bubonic plague, rabies, and various viral infections, though Dr. Groves says instances of these are extremely rare in lab rats, which are raised in controlled environments. “I don’t know anybody who has ever had some consequence of being bitten by a rat,” he says.
Possibly the biggest problem working with rats is animal rights demonstrators. Dr. Groves calls them “narcissistic anthropomorphizers." Though he says the furor has died down a little, there was a time in the ’80s when demonstrators outside UCSD s medical teaching facility were not an uncommon sight. In 1988, Dr. Groves recalls, “My name was carried in effigy outside the building here.”
He adds, “Animal experimentation has become a dirty word, which is too bad because it’s such an error. It’s not that 1 believe animals don’t have rights. Of course they have rights. They have rights to humane treatment, and they have a right to live a humane life that does not involve torture or any kind of mistreatment. I have never known a scientist who would mistreat an animal. The animals we have here live happy, healthy lives, and they die painlessly.
The rat, for example, on which I want to do experiments is totally anesthetized so there is no torture, no degradation. I think I can speak for scientists as a group and say that we care as much about the health and care of animal subjects as animal rights people do, maybe more.”