[A preliminary study on mechanisms for urinary system disorders before and after ketamine withdrawal in rats]

To explore the mechanisms for urinary system disorders before and after ketamine withdrawal in rats and to evaluate the recovery degree of the urinary system damage after ketamine withdrawal.

Fifteen male healthy Sprague-Dawley rats were randomly divided into 3 groups: A control group, an experimental group, and a withdrawal group. The rats in the control group were given normal saline. The rats in the experimental group were given ketamine 30 mg/(kg.day) for 30 days. The rats in the withdrawal group were treated as the experimental group except for drug withdrawal for 2 weeks. In the experimental period, we randomly selected 1 rat of kidney, ureter, and bladder from each group to perform HE staining. The bladder tissues in each group were used to detect mRNA expression by quantitative real-time polymerase chain reaction (qRT-PCR).

1) The behavior of ketamine-injected rats was obviously changed, but the weight of ketamine-induced rats was not changed. 2) As compared with the control group, the experimental and withdrawal groups showed infiltration of mononuclear inflammatory cells in the kidney tissues, the thinner epithelium of bladder and infiltration of submucosal mononuclear inflammatory cells under the optical microscope. 3) As compared with the control group, the expression of H1R mRNA was increased in the experimental group (P<0.05). As compared with the experimental group, H1R mRNA expression was significantly decreased in the withdrawal group (P<0.05).

Ketamine abuse could induce behavior changes in rats. The infiltration of mononuclear inflammatory cells in kidney and bladder, the thinner bladder epithelial layer, and the increased H1R gene mRNA expression in bladder might be an important pathogenesis of KAUD. Ketamine withdrawal may effectively reverse the pathogenic process of KAUD.