Comparison of cannabinoids with known analgesics using a novel high throughput zebrafish larval model of nociception.

It has been established that both adult and larval zebrafish are capable of showing nociceptive responses to noxious stimuli; however, the use of larvae to test novel analgesics has not been fully explored. Zebrafish larvae represent a low-cost, high-throughput alternative to traditional mammalian models for the assessment of product efficacy during the initial stages of drug development. In the current study, a novel model of nociception using zebrafish larvae is described. During the recovery from an acute exposure to low levels of acetic acid, larvae display innate changes in behaviour that may be indicative of nociception. To assess the usefulness of this model for testing potential analgesics, three known synthetic pain medications were assessed (ibuprofen, acetaminophen and tramadol) along with three naturally occurring products (honokiol, tetrahydrocannabinol and cannabidiol). When the effect of each compound on both the acetic acid recovery and control activity was compared there appeared to be both similarities and differences between the compounds. One of the most interesting effects was found for cannabidiol which appeared to oppose the activity change during the recovery period of AA exposed larvae while having a nominal effect on control activity. This would appear to be in line with current research that has demonstrated the nociceptive properties of cannabidiol. Here we have provided a novel model that will complement existing zebrafish models and will expand on the potential use of zebrafish larvae for studying both nociception and new analgesics.

Working class membership and the adolescent identity crisis.

The purpose of this study was to compare the identity status of employed, working class youth with status frequencies reported by Marcia for middle class college students of the same age. Also, an exploratory content analysis was used to suggest factors that block and facilitate identity achievement within the working class group. Identity status ratings were obtained for twenty-eight working class males who were interviewed with Marcia's semistructured questionnaire. Comparisons revealed that the working class youth were more likely than the middle class youth to be in either an identity achievement or diffusion status, and less likely to be in a state of crisis or to have accepted the values of parents without question. Additionally, youth who had both experienced a crisis and resolved that crisis tended to perceive fewer blocks to the opportunity to take part in desired experiences or discussions than other youth. The research suggests that the development of identity may differ between social classes and that experiences outside of the family are significant influences on identity status.