The role of PLC-IP3 cascade on 4-aminopyridine (4-AP) contracture in electrically-driven rat atrial and diaphragmatic strips: new evidence by neomycin and heparin.

Induction of cardiac contractures by 4-AP in Ca2+-free medium implied the involvement of SR and PLC-IP3 cascade. Thus, the role of PLC-IP3 cascade against contractile actions of 4-AP in electrically-driven rat atrial and diaphragmatic strips were studied both in the presence, and absence of Ca2+ using neomycin, a PLC inhibitor, and heparin, an IP3-R antagonist. 4-AP was applied cumulatively in logarithmically increasing concentrations in the range of 1-16µg/ml, and the preparations were treated with neomycin (400µM) or heparin (400µg/ml) for 3min prior to 4-AP injection.

Investigation of the dose-dependent antivasospasmic effect of Ginkgo biloba extract (EGb 761) in experimental subarachnoid hemorrhage.

Many drugs with possible effects against the vasospasm that occurs following a subarachnoid hemorrhage continue to be investigated with great enthusiasm. Among these drugs, the effect of Ginkgo biloba extract (EGb 761) on vasospasm has not been studied extensively. A model of vasospasm was constructed using 30 selected Sprague-Dawley rats.