Comparative Study of the Neurotoxic Effects of Pregabalin Versus Tramadol in Rats

In Egypt, both pregabalin and tramadol misuse increased in the last decade. Although many studies have confirmed the neurotoxic effects of tramadol, those of pregabalin are understudied. The aim of the study is to evaluate the neurotoxic effects of pregabalin compared with tramadol. Thirty male albino rats were included in this experimental study, and they were randomly allocated into three equal groups: group I (normal saline), group II (tramadol misuse), and group III (pregabalin misuse). All rats received the commenced drugs for 1 month. Open field tests were performed on the day of scarification, and after that, cortical samples were taken for immunohistochemical analysis and quantification of dopamine receptors' gene expression. The drug misuse groups showed a significant decrease in weight gain at the end of the study. Open field testing showed the upper hand of controls regarding all of the tested parameters. Tramadol has a more negative impact on the locomotor parameters compared with pregabalin. Both drugs induced relatively low dopamine-1 receptor (D1Rs) expression to dopamine-2 receptors (D2Rs), mimicking the schizophrenia model. Both tramadol and pregabalin were associated with neurotoxic effects in male albino rats. These effects were less noticed with pregabalin. It is suggested that long-term abuse may end in psychosis.

Automated summary

Both pregabalin and tramadol misuse have increased in Egypt in the past decade. While the neurotoxic effects of tramadol have been well studied, research on pregabalin is lacking. This study aimed to compare the neurotoxic effects of pregabalin and tramadol. Experimental research was conducted on thirty male albino rats, divided into three groups: normal saline, tramadol misuse, and pregabalin misuse. After one month, the rats were evaluated through open field tests and analysis of cortical samples. The results showed that both drugs had neurotoxic effects, with tramadol having a greater impact on locomotor parameters compared to pregabalin. Additionally, both drugs led to low dopamine receptor expression, resembling a schizophrenia model. Pregabalin had less noticeable neurotoxic effects compared to tramadol. The study suggests that long-term abuse of these drugs may result in psychosis.