Fluconazole and dihydropyridine calcium channel blockers (DCCBs) are simultaneously used in clinical practice. Although fluconazole can increase the blood levels of DCCBs by inhibiting CYP3A4, there are only a few reports regarding the effects of interaction of these drugs on blood pressure. Based on electronic medical records, we conducted a retrospective study of blood pressure in hospitalized patients treated with fluconazole while receiving amlodipine and nifedipine. The mean blood pressure over 3 days, specifically 2 days before starting fluconazole treatment and the first day of fluconazole treatment (day 1), was used as the reference value to compare the mean blood pressure calculated every 3 days after day 1 until day 13. Most of the 26 patients included in the study had underlying hematologic malignancies. The average age of patients was 71.8 years. Twenty-one patients received amlodipine and five received nifedipine. The combination of DCCBs and fluconazole was associated with a significant decrease in blood pressure on day 11–13 (p < 0.01). The mean difference in overall systolic blood pressure was −15.8 mmHg (95% CI: −21.1 to −10.4). Therefore, the combination of fluconazole and DCCBs might potentiate the antihypertensive effect of DCCBs, and caution should be exercised when using them for lowering blood pressure.

GPR55 is a G protein-coupled receptor that is proposed as a novel type of cannabinoid receptor. Lysophosphatidylinositol is an endogenous ligand for GPR55. The physiological roles of GPR55 have not yet been elucidated in detail. In the present study, the expression of Gpr55 mRNA was evaluated in various mouse tissues and organs using real-time RT-PCR. Gpr55 mRNA expression was highest in testis, the male reproductive system, among mouse tissues. Gpr55 mRNA expression was high in immune organs such as the spleen, lymph nodes, and thymus. Gpr55 mRNA was also detected in the small and large intestines. The expression of Gpr55 mRNA was relatively low in a mouse brain. The distribution of Gpr55 in mice is very similar to that in humans, however, the rank order was somewhat different. The sub-fractionation revealed that Gpr55 mRNA was expressed in both germinal cells and somatic cells in the testis. In the small intestine, Gpr55 was expressed in the duodenum, jejunum, and ileum. Gpr55 was highly expressed in B and T lymphocytes and dendritic cells in the mouse spleen.