Stimulus functions of drugs and the assessment of abuse liability

The development of a unifying framework for conceptualizing the commonalities in various forms of substance abuse must encompass the data base focused upon the stimulus functions of drugs. In the first instance, for example, the research on drug self-administration has provided convincing evidence of a remarkable concordance between laboratory animals and human substance abusers in the reinforcing stimulus functions of a range of chemical agents. The recognition of these cross-species and cross-drug generalities has radically changed conceptualizations of substance abuse from a reactive to a more active process and has encouraged the kind of functional analysis of drug-seeking and drug-taking that has proven productive and useful in the study of other behavioral interactions. In this regard as well, recent refinements in the analysis of the discriminative stimulus functions of drugs have provided a more comprehensive basis for characterizing a chemical agent's spectrum of action and evaluating its abuse liability. While the correlation between the discriminative stimulus functions and the reinforcing stimulus functions is remarkably high for some drug classes, there are notable exceptions. Finally, the assessment of abuse liability requires an analysis of the eliciting stimulus functions of drugs as reflected by the physiological and behavioral changes, both acute and chronic, that follow drug administration. The methods used to evaluate both physiological dependence and behavioral toxicity in relationship to sensory and motor effects for a range of abused drugs have depended heavily upon an assessment of the eliciting stimulus functions of such compounds.     

A programme for treating chemically dependent medical students

Summary. The first American programme for chemically dependent medical students at the University of Tennessee, Memphis is described. The goals of the Aid for the Impaired Medical Student (AIMS) Program are to provide confidential treatment for chemically dependent medical students, to assure that recovering students are able to resume their education, and to protect patients and others from the harm that may be caused by impaired students. The Program is administered by the AIMS Council, consisting of medical professionals and elected student representatives. The Council oversees the management of cases, including investigation of students who may be impaired, intervention when chemical dependency is suspected, diagnostic evaluation, treatment and aftercare, and post-recovery advocacy for students. The Program's experience includes 18 cases of suspected chemical dependency, with four self-referrals and 14 students referred by third parties. Eleven students have been diagnosed as chemically dependent and have completed treatment programmes. Nine have maintained recovery and eight have graduated. One student subsequently relapsed and committed suicide. Obstacles in programme implementation have involved absence of perceived need, the view that chemically dependent students should be dismissed from school, and reluctance of students to report classmates. Resources have included highly respected student representatives, a supportive administration, assistance of the impaired physicians programme, and medical insurance and professional courtesy to defray costs. Although the number treated has been modest, the AIMS Program is an important vehicle for training students regarding chemical dependency and their professional obligations toward impaired colleagues.     

New South Wales Nurse Education Project

Abstract: The development of a teaching package for nurse educators on drug and alcohol problems is described and the contents of its 16 modules outlined.     

Graduate Education in the Field of Substance Abuse

Abstract: Twenty-six part-time students from a variety of professional backgrounds are enrolled in the first year of a Graduate Diploma in Social Science (Drug Dependence) at the Phillip Institute of Technology in Victoria. The course is conducted under the auspices of the School of Social Work and commenced in 1984. It is argued that the graduates from this unique course could play a key role in providing personnel to fill positions in the areas of clinical work, staff development, drug education, programme development and management and research.     

呋喃唑酮厌恶疗法戒酒的初步报告

对8例酒精依赖伴中毒男性患者,采用呋喃唑酮结合小量饮酒方法进行临床观察,因其产生不良躯体反应而达到厌恶戒酒目的。其成功率为87.5%。远期不良反应轻微。戒酒机制可能属厌恶条件反射的建立。     

Potassium-selective channels in the basolateral membrane of single proximal tubule cells of frog kidney

The membrane potential of proximal tubule cells is dominated by the potassium conductance of the basolateral membrane. In the present paper the nature of this conductance is investigated by the patch-clamp technique. Only one type of K channel was found in the basolateral membranes of freshly isolated proximal cells. In cell-attached patches, the current/voltage relationship is markedly non-linear with much larger inward (30 pS) than outward ( 6 pS) conductances, even in the presence of roughly symmetrical K concentrations. Thus the channels show inward rectification. The determination of the conductance for outward current flow is complicated since the current/voltage curves show an area of negative conductance. Nevertheless, taking the conductance for outward current flow and the density of the channels it is possible to account for all of the previously reported potassium conductance of amphibian proximal tubule cells. The open probability of the channels was found not to depend upon the membrane potential. However, the non-linearity of the current/voltage relationships will confer upon the channel the same voltage dependence as that seen in intact proximal tubules, i.e. the conductance decreases with depolarisation. Incubation of cells in Ringer with no substrates or in the presence of alanine and/or glucose showed no change in the activity of the channels. These findings suggest that, although these channels may represent the basolateral conductance of frog proximal tubule cells, they are not involved in the well-established coupling between transport rate and potassium conductance.This work was supported by the Wellcome Trust     

Prevention of precipitated withdrawal symptoms by activating central cholinergic systems during a dependence-producing schedule of morphine in rats

Previous studies in this and other laboratories have suggested an important role for central cholinergic neurons in the expression of morphine withdrawal symptoms. This study was designed to determine whether the symptoms of withdrawal could be mitigated by normalization of the effect of morphine on cholinergic neurons. Since this effect is generally inhibitory, we used centrally acting cholinergic agonists to augment central cholinergic tone during chronic morphine infusion. Rats were made dependent following the intra-arterial (i.a.) infusion of increasing concentrations (35-100 mg kg(-1) day(-1)) of morphine over 5 days. I.a. injection of 0.5 mg/kg of naloxone precipitated a profound withdrawal response that included a dramatic increase in mean arterial pressure (MAP) which was maintained over the 60-min observation period, a short duration increase in heart rate (HR), and characteristic opiate withdrawal symptoms. In separate groups of rats, non-toxic doses (50 and 250 microg/kg) of the acetylcholinesterase (AChE) inhibitor, diisopropylflurophosphate (DFP) were administered as single daily injections concomitant with the morphine infusion. DFP treated rats, exhibited significantly reduced expression of the naloxone-evoked pressor response. The apparent anti-withdrawal effect of DFP was not reproduced by the selective peripherally acting AChE inhibitor, echothiophate, although both compounds effectively reduced the expression of certain other withdrawal symptoms. The centrally acting muscarinic cholinergic receptor agonist, arecoline, resulted in an even more impressive suppression of withdrawal symptoms. While not all symptoms associated with morphine withdrawal are mediated via central cholinergic pathways, these results suggest that physical dependence on morphine can be suppressed to a significant degree by the augmentation of central cholinergic activity during morphine administration.     

120例男性酒精依赖患者复饮的相关因素分析

目的 探讨男性酒精依赖患者复饮的相关危险因素.方法 选取2018年7月1日至2019年6月30日在我科出院的男性酒精依赖患者,回访出院6个月内是否复饮,分为复饮组和未复饮组,收集两组相关临床资料并进行统计学分析.结果 120例男性酒精依赖患者出院6个月内复饮49例,复饮率40.83％,患者饮酒年限、饮酒量、戒断是有无幻...