Reinforcing effects of fentanyl analogs found in illicit drug markets.

Rationale: The potent synthetic opioid fentanyl, and its analogs, continue to drive opioid-related overdoses. Although the pharmacology of fentanyl is well characterized, there is little information about the reinforcing effects of clandestine fentanyl analogs (FAs).

Objectives: Here, we compared the effects of fentanyl and the FAs acetylfentanyl, butyrylfentanyl, and cyclopropylfentanyl on drug self-administration in male and female rats.

Reinforcing effects of phenethylamine analogs found in dietary supplements.

Rationale: Synthetic phenethylamine (PEA) analogs, such as β-methylphenethylamine (BMPEA) and N,α-diethylphenethylamine (DEPEA), are often found in dietary supplements, despite regulations prohibiting their sale. PEA analogs are structurally related to amphetamine, and we have shown that BMPEA and DEPEA produce cardiovascular stimulation mimicking the effects of amphetamine. However, few studies have examined behavioral effects of BMPEA, DEPEA, and other PEA analogs.

Automated Computer Software Assessment of 5-Hydroxytryptamine 2A Receptor-Mediated Head Twitch Responses from Video Recordings of Mice.

Psychedelics are a class of drugs that produce unique subjective effects via agonist actions at the 5-hydroxytryptamine 2A receptor (5-HT). The 5-HT-mediated head twitch response (HTR) in rodents is used as a reliable proxy for psychedelic drug activity in humans, but existing methods for measuring HTRs require surgery or time-consuming visual scoring. In the present work, we validated a simple noninvasive method for quantitating HTRs using computer-based analysis of experimental video recordings.

Optimal Endocrine Evaluation and Treatment of Male Infertility.

This article aims to define the optimal endocrine workup of male factor infertility, including evaluation and treatment of men who have previously been on exogenous testosterone or anabolic steroids. Future directions include the expansion of genetic testing for infertility to include endocrine gene products.