Pharmacological profile of hydroxy fasudil as a selective rho kinase inhibitor on ischemic brain damage.

The neuroprotective property and the effects on hemodynamics of hydroxy fasudil, an active metabolite of an antispastic drug, fasudil, were examined. In rats, hydroxy fasudil was found following intravenous infusion or intraperitoneal administration of fasudil, and the maximum plasma concentration of hydroxy fasudil was approximately 25 or 40% of the parent drug, respectively. The i.v. administration of hydroxy fasudil produced significant increases in regional cerebral blood flow in dogs. Hydroxy fasudil relaxed the KCl, PGF2alpha or U-46619-induced contraction in canine basilar or middle cerebral arterial strips, concentration-dependently. The neuroprotective property of hydroxy fasudil was examined on delayed neuronal death in gerbils. Hydroxy fasudil (3 mg/kg) significantly protected against the ischemia-induced neuronal loss. To further clarify the effect on neurological impairments, hydroxy fasudil was tested in a rat model of microembolization stroke. Intravenous administration of hydroxy fasudil improved neurological functions, significantly reduced the size of the infarct area and prevented the accumulation of neutrophils. The present findings suggest that hydroxy fasudil has an efficacy to improve the hemodynamic function and to inhibit neutrophil-mediated damage, and contributes to the potency and long duration of the cytoprotective properties of fasudil on ischemic brain damage, and also suggest a critical role for rho kinase in the pathogenesis of cerebral ischemic injury, and the potential utility of rho kinase inhibitor as a therapeutic agent in stroke.

[Clinical evaluation and problem of intra-arterial infusion chemotherapy of liver metastasis from digestive organ cancer].

Intra-arterial infusion chemotherapy using an implantable reservoir was used for 22 patients with liver metastasis from September 1986 to March 1990. The material consisted of 8 subjects with gastric cancer and 14 with colorectal cancer. One had metastasis in one lobe (H1), 10 had a few scattered metastases in both lobes (H2) and 11 had numerous metastases in both lobes (H3). In 5 cases, a reservoir was implanted to prevent the recurrence after hepatectomy. Infusion catheter was placed in the proper hepatic artery in 5 cases via the gastroduodenal artery at laparotomy and it was carried out subcutaneously via the femoral artery in 17 cases. In all cases intra-arterial infusion of 5-FU was continuously administered followed by intermittent one shot injection of ADM. The clinical effectiveness of the therapy was well evaluated. One-year cumulative survival rate of all cases by Kaplan-Meier method was 55% and that of H2 cases was 78%. No recurrence was noted in post hepatectomy cases. Eight cases (36.3%) showed remarkable complications, which made it impossible to continue intra-arterial infusion chemotherapy: hepatic artery occlusion (3 cases), infection (2 cases), abdominal pain (1 case), hematoma in the implanted site (1 case) and dislocation of the infusion catheter (1 case). From the present study, it is considered that intra-arterial infusion chemotherapy is a useful procedure for the control of liver metastasis. Regimens for improved chemotherapy and the maintenance of more useful and safer catheters should therefore be investigated for further development of the therapeutical estimation.

Vitamin A protects the small intestine from methotrexate-induced damage in rats.

A protective effect of vitamin A (VA) against cytotoxic antitumor drug-induced damage of rat small intestine was found. Oral administration of methotrexate (MTX) for the small intestinal mucosa of rats resulted in a severe histological change, whereas rats coadministered VA with MTX showed a histological status similar to that of control rats. The p.o. administration of MTX led to a decrease in the amounts of membrane proteins and lipids in rat small intestine and its brush border membrane. When administered p.o. with VA, this decrease failed to occur. The brush border membrane of MTX plus VA-treated rats, when monitored by the fluorescence of cationic safranin O and anionic 8-anilino-1-naphthalenesulfonic acid, was found to resemble that from control rats rather than that from MTX-treated rats. The in vitro permeation of MTX in the small intestine of MTX plus VA-treated rats was enhanced, in contrast with the decrease noted for MTX-treated rats. However, that of untreated rats was not affected by the presence of VA. Thus, VA is unlikely to affect the transport process of MTX directly. When administered p.o. with VA, MTX was absorbed effectively to the same or a slightly greater extent than when administered by itself. Consequently, it has been shown histologically, biochemically, physicochemically and physiologically that VA protects the small intestine from the damage induced by MTX.

Change in small intestinal brush border membranes of rats following methotrexate administration.

Change in small intestinal brush border membranes of rats following methotrexate administration was monitored by the fluorescence spectra and polarization of the cationic fluorescent probe, safranin 0. Total protein content of brush border membranes of treated rats was less than that of control rats, whereas no significant difference in total sialic acid content of brush border membranes was observed between them. Thus, an apparent increase in the electronegative charge of brush border membrane vesicles per unit of membrane protein following methotrexate administration may possibly cause the change in fluorescence spectra and polarization of safranin 0.