Narcotics research, rehabilitation, and treatment. Hearings, Ninety ...

Narcotics research, rehabilitation, and treatment. Hearings, Ninety ... Narcotics research, rehabilitation, and treatment. Hearings, Ninety ...

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490In the lower two graphs are ilhistrated experiments in which theanimal ^^ as taking codeine alone, to your left, in which he made abouta thousand bar presses to get 30 injections of codeine, and then hisbehavior in 1 day in which he was pretreated with an injection ofnaloxone. When he was pre treated with naloxone he bar pressed afew times, about 50 times, and quit immediately. There was no morebar pressing in spite of the fact the drug was available to him.Mr. Brasco. Doctor, naloxone is not a substance upon which onebecomes dependent?Dr. ViLLARREAL. That is correct.Mr. Brasco. In the case of this monkey, after he was given a doseof naloxone, he did not bar press.Dr. ViLLARREAL. That is right.Mr. Brasco. Now, how did he come to bar press again when youtook the naloxone away? I do not understand that. If you are notdependent on naloxone it would seem to me that that would be asuccessful treatment for taking someone off drugs and havmg themdrug free. I do not get the relationship of his bar pressing again.Dr. ViLLARREAL. Perhaps I can answer jour question this way.When the animal is switched from any drug to an inert substance, tosaline, just physiological solution, the animal quits bar pressing. Andwhat we have done with the pre treatment of naloxone is to rendercodeine totally ineffective so that the self-injections of codeine arelike self-injections of physiological saline. There is no longer an Althingm the syringe.Mr. Brasco. So, he does not bar press at all.Dr. ViLLARREAL. He probes a little bit as you saw at the beginningof the session, because he has all this drive but when there is noeffect, he quits.Mr. Brasco. Then, how does he go back to bar pressing again,because the apparatus gives him another shot of an addictive substanceor does he do that by accident?Dr. ViLLARREAL. He will do that by accident or by the strength ofthe habit of bar pressing behavior.[Slide]Dr. ViLLARREAL. These few slides that come next mil get to thepoint I think you are driving at. These are graphs of successive daA'sin which the monkej s are taking codeine. The}' are taking about 60injections a day. The monkey takes about 65, 58, 52, and so on,injections a day. This goes on for months and months.On this day we treat him with naloxone and he quits. He quits for2 days. Only on the first day he got naloxone. But then a little bit ofexploration, a little bit of probing on the bar, brings him back toexperience the full effects of codeine. So, as codeine is available againhe goes back to the previous behavioral base line.Mr. Brasco. The point is this. After the naloxone treatment hestill has the physiological urge for the drug.Dr. ViLLARREAL. YcS.Mr. Brasco. So than naloxone would be something that would haveto be given steadily also.Dr. ViLLARREAL. That is right.Mr. Brasco. As methadone.

491Dr. ViLLARREAL. Until the reflex dies out completely. One shot ofnaloxone is suflacient to block the drive for self-administration on thatda}^ but continued treatment would be necessary to block it completely.Mr. Brasco. Do we know how long the continued treatment wouldbe?Dr. ViLLARREAL. No.Mr. Brasco. Thank you.Mr, Winn. Have you tried continued treatment for as long as 30days?Dr. ViLLARREAL. No ; we have not done that yet.[Slide]Dr. ViLLARREAL. This graph illustrates that the same thing occurswith the other drugs of the narcotic class. Again you have a baselineof self-administration of pentazocine for 5 days and then on 1 daythe animal is treated with naloxone and then for 7 days the animal doesnot return to bar pressing but then at the eighth day he goes back upagain.[Slide]Dr. ViLLARREAL. This is just dose response curves, how muchnaloxone is needed. Before we can get to the point of investigatinghow long a treatment must be, we have to investigate a number ofother variables, like what dose ratios are important, how much naloxonewill antagonize, how much of what narcotic, whether or not theanimals have to have the drug around the clock or whether intermittentadministration of the antagonists will be sufficientThese are questions that are easy to ask but take a long time toresolve in the laboratoiy. Each one of the experiments shown in thisgraph took about a year to do.Mr. Winn. Doctor, have you tried any other inert substance otherthan saline?Dr. ViLLARREAL. We have tried a whole lot of other drugs thatdo not produce psychological dependence.Mr. Winn. Can 3'ou give the committee several examples?Dr. ViLLARREAL. Well, cyclazocine is one example of a drug thatis not self-administered. If an animal is, say, taking cocaine, which isa very strong dependence-producing drug and he is switched tocyclazocine, he quits immediately.Mr. Winn. Just like the experiments that you have had withsaline.Dr. ViLLARREAL. That is right. The same thing happens with othernarcotic antagonists such as nalorphine, levallorphan. The samething happens with phenothiazine, drugs used as major tranquilizers.Mr. Winn. They just do not turn them on. The}' stop pressing thebar because they have no desire for those because they get no resultsfrom them: is that right?Dr. ViLLARREAL. That is right.Mr. Perito. Please continue.Dr. ViLLARREAL. I think I will stop with the slides here.Mr. Perito. Doctor, could you, for the benefit of the committee,give a brief summary of your conclusions as a result of studying thiscompulsive self-administration behavior in m.onke.ys?Dr. ViLLARREAL. Ycs. I believc that the conclusions are tremendouslyimportant. Conclusion No. 1 would be that we have a very

491Dr. ViLLARREAL. Until the reflex dies out completely. One shot ofnaloxone is suflacient to block the drive for self-administration on thatda}^ but continued <strong>treatment</strong> would be necessary to block it completely.Mr. Brasco. Do we know how long the continued <strong>treatment</strong> wouldbe?Dr. ViLLARREAL. No.Mr. Brasco. Thank you.Mr, Winn. Have you tried continued <strong>treatment</strong> for as long as 30days?Dr. ViLLARREAL. No ; we have not done that yet.[Slide]Dr. ViLLARREAL. This graph illustrates that the same thing occurswith the other drugs of the narcotic class. Again you have a baselineof self-administration of pentazocine for 5 days <strong>and</strong> then on 1 daythe animal is treated with naloxone <strong>and</strong> then for 7 days the animal doesnot return to bar pressing but then at the eighth day he goes back upagain.[Slide]Dr. ViLLARREAL. This is just dose response curves, how muchnaloxone is needed. Before we can get to the point of investigatinghow long a <strong>treatment</strong> must be, we have to investigate a number ofother variables, like what dose ratios are important, how much naloxonewill antagonize, how much of what narcotic, whether or not theanimals have to have the drug around the clock or whether intermittentadministration of the antagonists will be sufficientThese are questions that are easy to ask but take a long time toresolve in the laboratoiy. Each one of the experiments shown in thisgraph took about a year to do.Mr. Winn. Doctor, have you tried any other inert substance otherthan saline?Dr. ViLLARREAL. We have tried a whole lot of other drugs thatdo not produce psychological dependence.Mr. Winn. Can 3'ou give the committee several examples?Dr. ViLLARREAL. Well, cyclazocine is one example of a drug thatis not self-administered. If an animal is, say, taking cocaine, which isa very strong dependence-producing drug <strong>and</strong> he is switched tocyclazocine, he quits immediately.Mr. Winn. Just like the experiments that you have had withsaline.Dr. ViLLARREAL. That is right. The same thing happens with othernarcotic antagonists such as nalorphine, levallorphan. The samething happens with phenothiazine, drugs used as major tranquilizers.Mr. Winn. They just do not turn them on. The}' stop pressing thebar because they have no desire for those because they get no resultsfrom them: is that right?Dr. ViLLARREAL. That is right.Mr. Perito. Please continue.Dr. ViLLARREAL. I think I will stop with the slides here.Mr. Perito. Doctor, could you, for the benefit of the committee,give a brief summary of your conclusions as a result of studying thiscompulsive self-administration behavior in m.onke.ys?Dr. ViLLARREAL. Ycs. I believc that the conclusions are tremendouslyimportant. Conclusion No. 1 would be that we have a very

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