Administration of Kampo medicine through a tube at an advanced critical care center.

n emergency and critical care medical centers, tube administration is employed for patients who have difficulty swallowing oral drugs owing to decreased consciousness or mechanical ventilation. However, tube clogging due to drug injection is a concern. We compared the crushing method with the simple suspension method for the passage of amlodipine, an antihypertensive drug, in combination with rikkunshito, which has been used to treat upper gastrointestinal disorders such as functional dyspepsia and gastroesophageal reflux in emergency and critical care medical centers, to ascertain the effect of Kampo products on the passage of other drugs during tube administration. When the crushing method was employed, poorly water-soluble solid products were formed, while a uniformly dispersed suspension was obtained using the simple suspension method. In addition, the passage rate of amlodipine through the tube was 64% and 93% in the crushing and simple suspension methods, respectively, thereby indicating that the simple suspension method provided more favorable than the crushing method. The results of this study suggested that the passage rate of amlodipine for patients who received Kampo products concurrently was higher when the simple suspension method was used, and an appropriate drug amount might well be able to administered to patients using this method. J. Med. Invest. 65:32-36, February, 2018.

Effect of GBR12909 on affective behavior: distinguishing motivational behavior from antidepressant-like and addiction-like behavior using the runway model of intracranial self-stimulation.

RATIONALE: It was recently demonstrated that the priming stimulation effect (PSE) in the runway model of intracranial self-stimulation (ICSS) can be used as a model system to study the motivational effects of drugs. However, the characteristics of this novel experimental model have not been fully clarified. OBJECTIVE: To elucidate the involvement of dopamine uptake inhibition in motivated behavior and the difference in experimental characteristics between closely related experimental models, we investigated the effects of the dopamine uptake inhibitor GBR12909 in the runway ICSS model, in the forced swimming test (FST), and on conditioned place preference (CPP). In addition, the role of dopamine receptor signaling in the runway model was evaluated using dopamine receptor agonists and antagonists. RESULTS: GBR12909 dose-dependently increased running speed on the runway and decreased immobility time in the FST without affecting the time spent in the drug-associated compartment in CPP tests. The effect of GBR12909 in the runway model was inhibited by pre-treatment with the dopamine receptor antagonists haloperidol and raclopride. The dopamine receptor agonists SKF38393 and quinpirole dose-dependently decreased running speed. CONCLUSIONS: These results demonstrate that GBR12909 displays motivation-enhancing and antidepressant-like effects without place conditioning effects. In addition, the mechanisms of PSE enhancement in the runway ICSS model are different from those underlying closely associated experimental models and are mediated by increases in dopamine signaling.

A new method for evaluation of motivational effects of drugs.

Motivation is a process that continuously changes behavior to achieve a goal and can be conceptualized as a series of steps relating to that process. Intracranial self-stimulation (ICSS) behavior is considered to consist of reward and motivational effects. Moreover, priming stimulation of ICSS behavior is known to promote motivational effects. Using the runway method and priming stimulation, rewards and motivational effects of ICSS behavior can be differentiated. We investigated whether the runway method and priming stimulation of ICSS behavior could be used to evaluate motivational effects of a drug. In the ICSS runway model, running speed was considered as a reference of motivational effect. An assessment of pharmacological drugs known to influence motivational states was also undertaken. Using our experimental methods, prominent changes were observed in running speed when animals were administered methamphetamine and nicotine. Based on our results, we conclude that the runway method may be useful for the evaluation of substances that affect motivation. This review introduces 4 types of neuronal processes involved in motivation, reward mechanisms, outlines evaluation methods, and describes motivational properties of psychoactive drugs.