e282 Abstracts / Drug and Alcohol Dependence 146 (2015) e202–e284

illegal psychostimulants themselves become legally controlled. Thepurpose of these experiments was to determine whether severaluncontrolled cathinone compounds, which are currently sold onthe gray market, stimulate motor activity and have similar dis-criminative stimulus effects as the widely abused psychostimulantscocaine and methamphetamine.

Methods: Pentedrone (�-methylamino-valerophenone), alpha-PBP (alpha-pyrrolidinobutiophenone) and alpha-PVP (alpha-pyrrolidinopentiophenone) were tested for locomotor stimulanteffects in male Swiss-Webster mice and subsequently for substitu-tion in male Sprague-Dawley rats trained to discriminate cocaine(10 mg/kg, i.p.) or methamphetamine (1 mg/kg, i.p.) from saline.

Results: Pentedrone, alpha-PBP and alpha-PVP produced loco-motor stimulant effects with efficacy comparable to those ofcocaine or methamphetamine. Effects were apparent by 10 minafter administration and lasted 3–5 h. Pentedrone, alpha-PBP andalpha-PVP each produced discriminative stimulus effects compa-rable to those of cocaine and methamphetamine.

Conclusions: These three compounds produced behavioraleffects quite similar to those of cocaine and methamphetamine andare thus likely to have similar abuse liability.

Financial support: Supported by NIH N01DA-13-8908.

http://dx.doi.org/10.1016/j.drugalcdep.2014.09.232

Influence of sex on gray matter volumedifferences between smokers and nonsmokers

T.R. Franklin, R. Wetherill, K. Jagannathan, B.Johnson, J. Mumma, N. Hager, H. Rao, A. Childress

University of Pennsylvania, Philadelphia, PA, UnitedStates

Aims: Studies have examined the effects of chronic smok-ing on the brain by comparing gray matter volume (GMV)in cigarette smokers to nonsmoking controls with inconsistentresults. Although the studies highlight the adverse effects of smok-ing on brain structure, sex differences were not examined, whichmay contribute to the conflicting findings. Thus, the current studyexamined GMV differences between smokers and non-smokers andassessed differences separately in males and females. Given thepotential toxic effects of tobacco smoke on brain morphology, weexpected that heavy smoking, as defined by pack years would beassociated with decreased GMV.

Methods: High-resolution structural data were obtained from82 (41 male) nicotine-dependent individuals and 85 (46 male)matched healthy controls. Statistical parametric maps were createdin SPM8 to perform between-group comparisons using the GM tis-sue segmentation output by DARTEL. A GLM was created with group(smokers vs. controls) and sex as factors of interest and voxel-basedwhole-brain GMV as the dependent measure. Covariates includedage and global GMV.

Results: Smokers showed reduced GMV in the thalamus andgreater GMV in the putamen, parahippocampus and lingual,fusiform and precentral gyri than controls. In smokers, there wereno sex differences in GMVs that met corrected thresholds. Femalesmokers had lower GMV than female controls in the thalamus.Male smokers had less GMV than male controls in the thalamusand cerebellum. Male smokers had greater GMV than male con-trols in the para-hippocampus and lingual, fusiform and precentralgyri. Greater number of pack years was associated with lower GMVin the thalamus of male smokers only.

Conclusions: GMV differences were greatest in the thalamus,which has the highest density of nicotinic receptors of any brainregion and thus is a prime target for morphometric anomalies that

may be associated with nicotine consumption. Alternatively, andnot mutually exclusive, perhaps this region is particularly suscep-tible to one or more of the numerous toxins in cigarette smoke.

Financial support: NIDA.

http://dx.doi.org/10.1016/j.drugalcdep.2014.09.233

Formal and informal organizational activities ofpeople who inject drugs

Samuel R. Friedman, Enrique R. Pouget, MilagrosSandoval, Yolanda Jones

National Development and Research Institutes, NewYork, NY, United States

Aims: People who inject drugs (PWID) are often seen only interms of their drug use—but they are first and foremost people. Peo-ple’s organizational involvements and activities may shape theirthoughts and risks (Friedman et al., 2013).

Methods: 300 PWID were recruited by referral from the NYCNational HIV Behavioral Surveillance study in 2012–2013. Each wasasked to list up to 5 types of formal and 5 types of informal groupsthey were involved in the last year. We tested selected associationsof group membership with drug and sex behaviors by sex with �2.

Results: 72% took part in one or more group. The most com-mon group involvement was with harm-reduction groups (28%).Among commonly reported formal groups were religious groups(6%), women’s groups (11% of women), men’s groups (6% of men),support groups (e.g., NA, AA; 14%), and groups (including supportgroups) at probation or parole departments (17% of men, 8% ofwomen, p < 0.05). 3% took part in occupy or other demonstrationgroups. 10% were part of an “informal hang-out” group. Of 29 PWIDwho took part in informal hang-out groups, 15 spent >20 h a weekwith them. Of 83 in harm reduction groups, 12 spent >20 h a week intheir activities. Those in harm reduction groups were significantlyless likely to share injection preparation equipment (p < 0.05) orto backload (p < 0.05), and had fewer sex partners (p < 0.05). Theytended (p = 0.054) to be less likely to engage in any unprotectedsex. Informal hang-out group membership was positively associ-ated with giving others a syringe that you already injected with(p < 0.05).

Conclusions: Most PWID take part in some sort of group activ-ities. Harm reduction groups are well-developed in New York:participation with them is reported frequently by PWID. Member-ship in them is associated with lower self-reported injection and,perhaps surprisingly, sexual risk behavior—suggesting that harmreduction group activities may have formed a focal point or sub-culture of lower risk in a risky environment.

Financial support: NIDA grant R01 DA031597. The content issolely the responsibility of the authors and does not necessarilyrepresent the views of NIDA.

http://dx.doi.org/10.1016/j.drugalcdep.2014.09.234

The impact of HIV testing policies and practiceson HCV testing

Jemima A. Frimpong, T. D’Aunno, David M.Wutchiett, Lisa R. Metsch

Columbia University, New York, NY, United States

Aims: Hepatitis C (HCV) is the most common blood-borne infec-tion in the U.S. HCV recently surpassed HIV as a cause of deathin the US. The advent of new HCV testing techniques and treat-ments presents a promising platform to addressing the HCV burden.