| Description | This is the second part of an interview with Professor Kosterlitz recorded on 27 November 1985 by Elizabeth Olson.
Transcript of interview :
O You studied the autonomic nervous system in the '50s. What were you trying to find out?
HK This is not an easy question to answer. What I really wanted to get is a model outside the body where we could use isolated tissues in which we could investigate the actions of compounds which act on the autonomic nervous system… That… I was not… well, in the first instance I also did some work in the whole anaesthetised the animal, but for the analysis of the mechanisms you really always have to go down to smaller parts of the body and we used, we started to use at that time, isolated tissues in which you have substances in which will, for instance, cause a contraction of a piece of gut and we were quite early interested in substances which would prevent this action. You can also, for instance, electrically stimulate the gut and you get a contraction and we were interested in the substance. In that sense it is from the part of, when we use drugs it's pharmacology. If we investigate the mechanism you could say it's physiology.
O So you were looking at both fields, from a quick glance at your papers?
HK Yes, I mean it was really that, you cannot distinguish the autonomic nervous system, when you investigate it, between physiology and pharmacology. Not really you know. You may look at the physiological mechanisms but the compounds we used to vary their normal mechanisms are almost always of a pharmacological nature unless it is a substance which is released by the cells of the autonomic nervous system. Like for instance acetylcholine.
O Which it releases itself. Yes.
HK Which is released when the gut is stimulated electrically or under physiological conditions. The acetylcholine is released from the nerve endings but, you see, you cannot investigate it, normally, without preventing… using other substance which will prevent the breakdown of acetylcholine because when acetylcholine is released, it is at a receptor. Quite close to the receptors are enzymes which destroy the acetylcholine so you use either, substances which will prevent these enzymes from acting, or you use, not physiological compounds which are stable, which are not affected by the cholinesterase as we call this enzyme which destroys it. That is a very general technique for investigation, that you either prevent enzymes or you use a substance which is stable. With the opiates too, it all leads to the same thing.
O And where did your initial work in the '50s lead you? What was it that made your work suddenly expand?
HK Well I was interested in the reflex of the gut when you filled the lumen of the gut. And I was stimulated by the work of Trendelenburg, which we have already mentioned, who did some very fundamental work on that. I mean, he isolated a piece of small intestine of the guinea pig and filled fluid in it and then you got a peristaltic wave which expelled the fluid and I was interested in the mechanism of that and there are a number of compounds which will prevent this peristaltic reflex, as for instance, noradrenaline and morphine. But Trendelenburg has known all that, but he didn't, at that time, investigate the mechanisms in detail.
O He'd have just made the observation that these things happened?
HK Well, yes. Well that is, he started to investigate the mechanism but he didn't have the possibilities of doing it in more detail, as we could do it.
O Because of the primitive techniques of the time...?
HK Well or...
O ... the earlier techniques of the time?
HK Yes, not primitive…!
O I'm sorry, I beg your pardon.
HK Yes. Well you always do it like that. When you look at something new you will always use simple techniques. I would rather use the word simple.
O Sorry.
HK No, this is quite an important thing. Simple techniques, because if you start off using elaborate techniques from the very beginning you put an awful lot of work into your experiments which may not lead to anything. If you use simple techniques, when you get a…, you know you get a response you can start using this as a basis to start off with. And Trendelenburg produced the basis of all the work you see and, it's then when we got interested in the action of morphine. How does it, in more detail, prevent…? But it is not necessarily morphine which does that in the gut but also noradrenaline, I mean the adrenergic system will also prevent that…
O Prevent the reaction that Trendelenburg was getting?
HK The distension of the lumen of the gut.
O I see, yes. Were other people working on this at the same time?
HK [Pause] Well, in the way I did it probably not, but Sir William Paton, well he's now Sir William Paton, he was then Bill Paton, he - I can't remember the exact time whether… it was very simultaneously - but what he did was, and was quite new, that he didn't use distension of the lumen of the gut, but he put an electrode inside the lumen of the gut, and one outside and stimulated it electrically through the wall and then he saw it contracted, in a different way. The longitudinal muscle just shortened. It wasn't a peristaltic wave as you get with distension. And he then looked for compounds which would prevent that, and he knew, of course, of Trendelenburg's work on morphine, and he tried morphine and tried many other compounds which are morphine-like which have been synthesised by industry. You see, one of the points with, you may ask now: why did industry spend so much time and money on finding other substances different from morphine? There are several reasons, but the two main reasons are that morphine itself is not very well… the stomach doesn't like it very much, it causes vomiting and that is the one reason. The other one, is that morphine in concentrations which give analgesia of pain relief will also cause depression of respiration. And at that time one didn't know, one really didn't know why it did that, because morphine was a compound, a drug from outside. You see we didn't know anything, whether it was present, anything like that was present in the, in the human, in our, body. It was obtained from the poppy, from the opium poppy, which is a very special poppy. And so industry wanted to find compounds which will not be so unpleasant to take and also if there were compounds which will give analgesia but will not depress respiration. Because this depression of respiration can be very dangerous. And any number of compounds have been synthesised, and in the early stages, pharmaceutical, say a company, they became very enthusiastic, saying 'Oh, we have a compound which is a good anaesthetic, but it doesn't cause respiratory depression,' but if they then waited a little bit and looked a little bit longer, particularly the usage in man, they caused respiratory depression. There is really no compound of the opiate variety which is a good analgesic that will, in doses which are used therapeutically, not cause depression of respiration which of course could be very dangerous. At that time I wasn't interested in the other effects of morphine. For instance, that it interferes with the endocrine system, which is now known after the enkephalins and so on, - particularly important you see. We didn't know anything about these things, what the other compounds would do. They were just undesirable side effects. We wanted to have a good analgesic which wouldn't do any harm and, of course, respiratory depression was particularly serious.
O So when did you…?
HK And that is…, no, I must just continue, and Bill Paton was interested to find out whether he could use his model of electrical stimulation of the gut to differentiate between the different synthetic opioids. He did find that the response he got, the degree of response, was quite closely correlated to their analgesic effect. In other words ,he got a bigger depression of the contractions when he had more analgesic effect in man, and so forth
O And that was commercially useful also?
HK Yes. And of course, I became, after he discovered that and showed that, I became very interested in it and I hesitated for quite a long time to use his technique. I continued to use distension and I used another preparation. The cat has a nictitating membrane, that is you know…
O A third eyelid, sort of thing.
HK Yes, which you can stimulate electrically and then will contract, and that is also inhibited by morphine like in the mouse. And I used these too because I didn't want to interfere with what Bill Paton was doing alone. But then sooner or later he was no longer interested in the opiates themselves but in their mechanism, what they do, in his particular preparation, so I felt at liberty to use his technique. That, of course, is the technique which has been used for all the work on opioids and a similar technique, namely the electrical stimulation of the [isolated] mouse vas deferens was used for the assay of the enkephalins. The reason why the mouse vas deferens was better than the guinea pig ileum or the myenteric plexus is because it is more sensitive to, we only knew that afterwards, to leucine-enkephalin and met enkephalin which are the two substances which are in a particularly large quantity in the brain. So, he had to use the mouse vas deferens rather than the guinea pig ileum for assaying his work. But we'll probably come to this later.
O Yes.
HK At that stage I decided I should concentrate on the action of opioid and opiate-like drugs on the autonomic nervous system. I had been in contact with the Committee on the Problems of Drug Dependence in the United States because they had a compound which is now used very widely, naloxone, you probably have heard of it...
O No.
HK You haven't? Naloxone. I got a sample of naloxone from the United States and we did a pharmacological analysis and we found that it was a selective antagonist of the action of morphine and we published that paper and I also then, when I visited the United States… the first time, I visited in particular, Dr Seevers.*
O Ah yes, of Michigan.
HK Of Michigan, yes, and as you see, at that time we used the peristaltic reflex of the guinea pig ileum and the cat nictitating membrane ,which I already mentioned in the assay of narcotic analgesics. I gave my talk and at the end, Dr Seevers - this is very true what I'm telling you now - said in his frank manner, very frank it was, which I learned to cherish later, 'Dr Kosterlitz, this has been very interesting. I'm afraid I cannot believe that such simple models are of real use'.
O Really? Yes.
HK I then asked him what I could do to convince him. 'Well if you are agreeable, I shall send you six [8] coded samples - that means samples without numbers - six coded samples for you to test. If you can assess the majority correctly I shall accept that there is something in what you told us today.' I was somewhat taken aback - not only somewhat - but agreed to his proposal. After my return to Aberdeen a packet arrived and we started to assay the substance with our models. Five of them did not cause us much trouble. One of them was likely to be morphine since it agreed in behaviour and potency with authentic morphine. But there was another compound which with the experience we had, up to that time, also seemed to be morphine. We sent Dr Seevers our results (I won't tell you what other compounds he sent to us) and to our surprise and satisfaction we were right in all but one of our findings. The exception was the second morphine-like compound which turned out to be nalorphine. Until then we had not studied compounds action which have both agonist and antagonist actions. Anyhow, nalorphine was one of those compounds so it behaved in our test like morphine because we only looked for the agonist and not for the antagonist action at that time.
O Yes, agonist is?
HK Agonist is when a compound does what it should do. In other words, say like morphine, it would prevent a contraction of the gut. The antagonist will prevent this action of the agonist so you if you put morphine in and use nalorphine, later on of course it was naloxone, this is the important thing, the morphine is, can't act that is an antagonist because it prevents the action of the agonist. That is the simplest way of putting it.
O And where did this lead you?
HK This of course… since Dr Seevers was a very important person in the States, from that point onwards he supported us. And not only that, but I was, (I forget now when that was, oh yes,) at the same time, as a matter of fact it was… before I saw Dr Seevers who was in Michigan, I first went to the laboratory of Julius Axelrod, who was a very famous man, a Nobel prize-winner and so on, and he decided to take me to lunch to the Cosmo Club in Washington and he said he would be very interested. I said I had not the faintest idea what it was going to be, and there I met Dr Nathan B. Eddy, who was the person in the States on opiates and, as I said here, he is 'the undisputed Nestor in the field of narcotic analgesics' which is quite true. And I learned, he really searched me very much and he could do that very well. It was impossible not to answer his questions directly you know, as you very often like to do, but he was quite fantastic in this respect and that was the beginning of a friendship. He was then, well in his seventies and he came to visit Aberdeen twice and that was very interesting. The first time he had... he had tried to do… I think we actually… yes, I had at that time the possibility of inviting people on behalf of the Medical Faculty, and so he came. And so he came. He gave a lecture. Now in this lecture, that was a long time ago, you see it was in the, I think it must have been in the middle seventies. Yes either the late '60s or the early '70s, probably '73, '74, something of that order, and (but I can check that) and he gave a lecture and he talked about - mind you that is why giving the date is so important - he gave a lecture on heroin and he warned his audience that heroin is a very dangerous drug and that it will lead to addiction. The late Professor Macgregor, in the discussion, got up and said, 'Dr Eddie, I find the talk very interesting but heroin is not a problem for us.' That is why the date is so important. Dr Eddie got up. 'Dr Macgregor, what you are telling me may be so, but I'm telling you that in a short time you will have a problem of heroin addiction.'
O That is true too.
HK Very true, very true indeed. And then he visited me again later on bringing his wife. I wondered why he wanted to visit me. I think what he did, he never said so, he came both times to look at the laboratory. He wanted to see, I think, how our work was getting on because I had asked for a rather, in the United States, to get a relatively large grant. I'm quite sure, he never said so and I've no real evidence for it, but I think he was trying to see whether it was worth supporting us.
O I've no doubt he was satisfied?
HK Yes, we got the money. Well that is the early history of how the whole investigation of opiates became really, in a way, supported and stabilised, and we got a standing, not so much in the world of this country, because heroin was of no importance and morphine, well everyone knew how to use morphine or some of the other compounds, but in particular in the States where it was of course a problem of addiction.
O It had started there?
HK The early addiction for long-term users. And though in this way our whole work became very important and they really supported us in every way they could.
O Was that support when you were in the Pharmacology Department?
HK No, I was still in Physiology.
O When you were still in Physiology that started, yes.
HK In the early days, '61, '62, yes. You see I began in the Pharmacology in '63 [1968], and so it was still at the Pharmacology Department in the early days, perhaps two or three years because I started a little bit, I can't remember now the exact date without thinking about it, but it was at that time that we had really become, thinking very seriously about the possibility of there maybe a compound in the body which is opiate like. And looking again at this, I don't know whether you saw that my friend Gordon Lees* apparently, I must have been talked about in '66, he thought I had...Wait a minute to see if I can find it [looks through notes] that is the difficulty, I'm so sorry about that now.
[Break in recording]
'Why did you do these experiments on a piece of nerve where you find, when you stimulate electrically you get deflections of the action potential?' and I was most hesitant to say why, but being a rather forceful young man, he was, how old could he have been, 19, 20?
O Something like that. He was a student doing a B.Sc. year in the middle of his medical school course, I think.
HK Yes, but he was a very forceful young man. He was the son, I mean his whole family is a very gifted family, and eventually I said, 'Well you know you shouldn't really ask, force me like this, but if you don't tell anybody else, I think there may be in the body a compound similar to morphine.'
O Which the body itself produces?
HK Which the body itself produces, yes.
O And how did you set about proving this?
HK Oh this comes later, much later. That was after I retired.
O The first time?
HK The first time yes. That actually, well I retired in '73. But in '72 I asked the National Academy of… no, the National Academy is … National… it's NIDA, I asked NIDA, let's just put it that I give you the word after, asked NIDA… [National Institute of Drug Abuse] whether we should ask again for more money. And they said, 'by all means'. And it was then that we decided, 'Now what are we going to do?' and I thought then, 'Now this is the time when shouldn't we think of endogenous opiate, endogenous that means in the body, compound?' and I asked John Hughes who was one of my lecturers at that time and at first he was a bit hesitant. He said, 'I don't know.' I mean I don't want to say too much about him because this is going to be public and I don't want to say anything more. Eventually, anyhow, what happened afterwards he came back to me and said, 'Yes, I'm going to join you.'
O How nice, yes?
HK And he had to give up his lectureship. We had to get money for him, and it was then, when we started in, after I retired, we got rooms here, because I had to give up my department of course, and for the first time we extracted from the brain of, whether it was sheep or ox I can't remember, the bovine brain probably [Pig]. John did all the work and it didn't take very long before - he used the mouse vas deferens - he could show there was a compound in the extract which would reduce the contractions and this reduction could be partially, not fully, reversed by the antagonist naloxone. And that was at that time already both for John and myself the absolute evidence that there was a morphine-like compound in the brain of these animals. The only difficulty there, was could it have been there accidentally, by the animal eating morphine? Which was most unlikely because it was high concentration. Or could it have been in the laboratory? But that was excluded because these experiments were done in a room where opiates have never been before. That was in 1973, the first indication that there was a compound like that and it took then until '75 to isolate that substance. It was awfully hard work.
O It was difficult to do, was it?
HK Yes, Well it was not only difficult to do. You had to use enormous numbers of brains ,of course ,and John had to go to... a that time I was, as I still am, a consultant with Reckitt and Coleman in Hull.
O That's a food firm is it?
HK Well, yes you know it as a food firm, but it is also a pharmacological firm. They have made drugs which are now used for pain relief, similar to morphine, which is known as buprenorphine and I persuaded them: 'Now, would you help us to extract these compounds and then get enough material from them to find out what is the biochemical or chemical composition of this compound?' Now the interesting thing was, and that is, you see this is all the kind of things which happen under these circumstances. But John did this hard work he got quite a bit of material coming back here and then he assayed it with his mouse vas deferens. He said, 'Hans, there's something very strange if you use these large quantities. We find two different compounds which, one looks like what we've seen before and if you don't know what it is, and the other one we also don't know what it is but it is different.' And I said to him, 'Well, I wonder, could it be - you have been working in Hull - could it be possible that you have some contamination there?' Because I knew they were making buprenorphine in a large scale and buprenorphine would just have done that same thing. So there was a very risky situation. But very fortunately if you look at it by its sensitivity to pH and its solubility in chloroform, different pH, it was quite different from number one.
O So you were fortunate that it wasn't the chemical that the factory were making.
HK Well, then we isolated it, we got more of this compound and sent it back to Hull and they identified it as buprenorphine. So we knew it was a contamination but you can imagine how worried we were?
O Yes, so it was the buprenorphine?
HK Buprenorphine which he picked up when he made all his extracts you see, because in that particular place buprenorphine was purified and isolated you see.
O I see and would they have used the same...?
HK No, no. It was in the walls or somewhere you see. We wouldn't know where it was.
O But it just contaminated your sample so that it was upsetting your result.
HK You see, the contamination is, of course, you mustn't forget, they made up about probably 10, 20 or 30 grams of morphine, 50 grams of the substance, and the contamination was of the order of one thousandth of a milligram. So you see it is quite easy to get a contamination. That is why one has to be so clean everywhere.
O So when you set up the Unit here, did...?
HK There was a Unit here already...
O Did you have to spend a lot of money on equipment?
HK Yes...
O And you had to set up?
HK We got that money from, to a great extent, it's American money, yes.
O And that would have meant that you...
HK National Institute of Drug Abuse, that's...
O Yes, that's the one you were looking for? And…
HK NIDA, you see?
O NIDA, yes you're right. So they would have given you money for equipment and they gave you money to fund yourself and your colleague John Hughes...?
HK And other people.
O And other people, yes?
HK I got a very large sum, over a period of three years and then of course, being a foreign institution, we had to reapply every three years.
O But you're obviously still getting it...
HK If we had been in the States... But you see, the interesting thing now is, because we had to write an application, you see, and there was enormous risk of what to say in the application. Now we knew that we were interested and they were interested in new… and opiate antagonists which one possibly could treat in heroin addiction, and so our programme was relevant enough, that we were going to investigate such antagonists.
O Yes, and did you?
HK Of course we did that too, but privately we also looked for the endogenous ligand! And about a year later I told them that there was an endogenous ligand and gave them the evidence and they were very excited and they said, 'That's fine, an extra year.' I don't know when we got more money but there was no problem with money at that time.
O At that stage yes. And an endogenous ligand is a morphine-like substance in the brain?
HK Which is made in the brain, manufactured in the brain, synthesised the brain, that is the important thing, you see. Because there is now, there is at the moment a problem whether or not the body can actually make very small quantities of morphine. It's just in the.... I wrote a note in Nature* about it, which is very interesting. I think... could you stop it for a moment?....because after this... a few years after the discovery of the enkephalins, it was found that they are derived from large peptides. Now you see there's a difficulty as how far one should go because this, it is rather important to acknowledge the people who did this work but I can't do that offhand, and we now know that there are three large precursors as we call it. The one is proopiocortin enkephalin, and the other one is proenkephalin and the third one is prodynorphin and they have all different functions. Now the first one, the proopiocortin enkephalin has beta-endorphin and also, in the same molecule, ACTH which is very important for many functions in the body. The second one, proenkephalin, has leucine-enkephalin and methionine-enkephalin and also other compounds of which one is of particular importance, namely - again I can't remember, I will write that down - and the third one, now, the leucine-enkephalin and methionine-enkephalin interact mainly with one of the receptors which is called the delta receptor but beta-endorphin and metorphamide (that's the one I couldn't get) and metorphamide enacts mainly with the mu receptor while the third one, the dynorphins they interact mainly with the kappa receptor..
O All in the brain cells?
HK All in the brain cells.
O In any particular part or do we know that?
HK Well, they are distributed in a different way in the brain. But that is really going a bit too far in detail. What I can say is probably a very high concentration of these compounds are in the hypothalamus which interacts closely with the pituitary and which controls many hormones. What the function of the kappa receptor is we do not know. Apparently part of the function of the mu receptor is control of pain, if you want to call it pain which is a difficult term to use because one really has to define what we mean by pain. And what the delta receptor does, again we don't know yet. So we are still very much at the beginning of that. But these are the fundamental, this is the fundamental situation now on which an enormous amount of work is being done at the moment. You can see the reprints lying all over the place, here, you see.
O From other centres or are they all from here?
HK No, no. They are from, this almost a complete... almost all reprints of all the papers on opioids. We have to collect them.
O Ah yes, from all over the world, from the people who are working on it. Are there other centres?
HK And you have got the ones coming from our Unit, I have given you that in my curriculum vitae?
O Yes, you gave me the list of them there.
HK There is, it's almost, I think there is only one, or perhaps one or two papers on which my name is not included because, you see what we did was, the people who do the work get their names first. I'm always at the very end.
O Oh sometimes not, but that is the principle?
HK No, if it is not, it's because its alphabetical. Some of the journals demand alphabetic order.
O What's the time lag between completing a paper and seeing it in print for you?
HK You mean after we have written a paper and say we send it away?
O Yes, do you expect it to come into print soon?
HK Yes, well the shortest time is four months. It is usually nine months, or plus, unless you have - sometimes when you go to a meeting you have what we call a pre-circulated communication - but yes usually…
O But the journals take longer?
HK Yes, you see in the pre-circulated communication one has to be very cautious because one does not want to give one's show away...
O No, it's difficult.
HK Because other people. You see, we never worried a lot but other people do. There are quite a number of people, particularly in the United States, who will not present anything unless they have it already in the press.
O Really, because of poaching perhaps?
HK Yes, the danger of somebody else doing it. And they, having spent a lot of time on it…
O Yes, I can understand that…Let's see…
END OF INTERVIEW
|