Distribution of Synthetic Cannabinoids JWH-210, RCS-4 and Δ 9-Tetrahydrocannabinol After Intravenous Administration to Pigs

Abstract

Background:Synthetic cannabinoids (SCs) have become an increasing issue in forensic toxicology. Controlled human studies evaluating pharmacokinetic data of SCs are lacking and only few animal studies have been published. Thus, an interpretation of analytical results found in intoxicated or poisoned individuals is difficult. Therefore, the distribution of two selected SCs, namely 4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210) and 2-(4-methoxyphenyl)-1-(1-pentyl-indol-3-yl)methanone (RCS-4) as well as ∆9-tetrahydrocannabinol (THC) as reference were examined in pigs.Methods:Pigs (n = 6 per drug) received a single intravenous 200 µg/kg BW dose of JWH-210, RCS-4, or THC. Six hours after administration, the animals were exsanguinated and relevant organs, important body fluids such as bile, and tissues such as muscle and adipose tissue, as well as the bradytrophic specimens dura and vitreous humor were collected. After hydrolysis and solid phase extraction, analysis was performed by LC-MS/MS. To overcome matrix effects of the LC-MS/MS analysis, a standard addition method was applied for quantification.Results:The parent compounds could be detected in every analyzed specimen with the exception of THC that was not present in dura and vitreous humor. Moderate concentrations were present in brain, the site of biological effect. Metabolite concentrations were highest in tissues involved in metabolism and/or elimination.Conclusions:Besides kidneys and lungs routinely analyzed in postmortem toxicology, brain, adipose, and muscle tissue could serve as alternative sources, particularly if other specimens are not available. Bile fluid is the most appropriate specimen for SCs and THC metabolites detection.

Time- and temperature-dependent postmortem concentration changes of the (synthetic) cannabinoids JWH-210, RCS-4, as well as ∆9-tetrahydrocannabinol following pulmonary administration to pigs

“…Thus, national and international guidelines recommend the standard addition approach for quantification of drugs in PM specimens (GTFCh 2018; Jickells and Negrusz 2008;Peters et al 2007;Skopp 2010;SOFT/AAFS 2006). Following this recommendation, this procedure has frequently been applied in quantitative PM studies on the tissue distribution of drugs (Hasegawa et al 2014;Mochizuki et al 2019;Schaefer et al 2017b;Siek and Dunn 1993). In particular in case reports of human fatalities the standard addition method has been used for PM analysis indicating that this is the prevailing analytical procedure in routine PM examination.…”

“…As already described in a previous study (Schaefer et al 2017b(Schaefer et al , 2019, 2 g solid tissue (brain, lung, liver, kidney, and muscle tissue) or bile fluid and duodenum content was homogenized (1 amount tissue/bile fluid/duodenum content + 4 amounts water). Subsequently, four 0.5-g portions were prepared with and without addition of different concentrations of JWH-210, HO-JWH-210, JWH-210-COOH, RCS-4, HO-RCS-4, RCS-4-COOH, THC, 11-HO-THC, and THC-COOH to create a standard addition calibration curve.…”

“…LC-MS/MS conditions including instrumentation, chromatographic, and mass spectrometric conditions for the analysis of extracts have already been described elsewhere (Schaefer et al 2015(Schaefer et al , 2017b(Schaefer et al , 2019. Briefly, a Thermo Fisher (TF, Dreieich, Germany) HPLC consisting of one Allegro pump, and an HTC PAL autosampler was applied.…”

Is adipose tissue suitable for detection of (synthetic) cannabinoids? A comparative study analyzing antemortem and postmortem specimens following pulmonary administration of JWH-210, RCS-4, as well as ∆9-tetrahydrocannabinol to pigs

“…PMI 1, (4 °C); PMI 1, (RT); PMI 2, (4 °C); PMI 2, (RT); PMI 3, (4 °C); PMI 3, (RT); in pig subcutaneous (s.c.), perirenal and dorsal adipose tissue (AT) following pulmonary administration of a 200 μg/kg body weight dose each. Concentrations are displayed as the median concentration change compared to concentrations calculated at PMI 0; RT room temperature Table 3 Data on basicity [pk a , (ChemIDplus 2020)], lipophilicity (logP, according to Schaefer et al (2017b)), ratio of maximum concentration in adipose tissue (C at ) and corresponding concentration in serum (C se ) according to Schaefer et al (2019) and adipose tissue storage index (ASI) calculated as a quotient of C at and relative administered dose of JWH-210, RCS-4, and THC; n.a. not available Cannabinoid pk a logP C at /C se ASI JWH-210 n.a.…”

EDITORIAL New Psychoactive Substances (NPS), a New Global Issue: Neuropharmacological, Chemical and Toxicological Aspects

“…Unlike ∆9-tetrahydrocannabinol, which is just a partial agonist of cannabinoid (CB) receptors, many SCs frequently act as full agonists on CB1 receptors and can cause unpredictable severe adverse effects even resulting in death. Schaefer and colleagues studied the distribution of two selected SCs, namely 4-ethylnaphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-210) and 2-(4-methoxyphenyl)-1-(1-pentyl-indol-3-yl)methanone (RCS-4) in pigs [ 11 ], whereas Huestis and her research group have focused on N-(1-amino-3,3-dimethyl-1-oxobutan-2-yl)-1-(4-fluorobenzyl)-1H-indazole-3-carboxamide (ADB-FUBINACA) an emerging synthetic cannabinoid whose toxicological and metabolic data are currently unavailable. They determined optimal markers for identifying ADB-FUBINACA intake, moreover metabolic stability was also evaluated with human liver microsome incubations [ 12 ].…”