dihydroergotoxine and eburnamonine

The effects of a new eburnamenine derivative (3 beta,14 alpha, 16 alpha)-(+/-)-14,15-dihydro-20,21-dinoreburnamenin-14-ol (vindeburnol, RU 24722) on EEG, on brain energy metabolism and on local cerebral blood flow (LCBF) and in different experimental models of cerebral insufficiency were compared with those of vincamine, vinburnine (1-eburnamonine), dihydroergotoxine mesilate and nicergoline. Vindeburnol at 2 mg/kg i.v., increased the EEG resistance time in rats subjected to asphyxia anoxia and at 10 mg/kg s.c., significantly improved the electrocortical recovery of gerbils subjected to a 10-min cerebral ischemia. Vindeburnol (10 mg/kg i.p.) significantly retarded glucose, phosphocreatine and adenosine triphosphate utilization and lactate production in mouse brain during 10 s of decapitation ischemia. The cerebral metabolic rate was 10.34 mmol/kg/min, which was about 50% of the control value. At 10 mg/kg i.p., the product induced a slight and transient increase in LCBF. Vincamine improved the early phase of the postischemic electrocortical recovery in the gerbil, had no effect on cerebral energy substrates and slightly increased the LCBF for 15 min. Dihydroergotoxine mesilate improved the early phase of the electrocortical recovery in gerbils subjected to ischemia, did not significantly modify the energy substrates and rapidly increased the LCBF, which was normal after 30 min. Vinburnine and nicergoline were inactive in the cerebral insufficiency models used and did not significantly modify cerebral energy metabolism. These results show that vindeburnol has a different pharmacological profile from vincamine, vinburnine, dihydroergotoxine mesilate and nicergoline, and suggest that vindeburnol may be therapeutically effective in cerebral insufficiency.

Topics: Animals; Brain Ischemia; Cerebral Cortex; Cerebrovascular Circulation; Cerebrovascular Disorders; Dihydroergotoxine; Electroencephalography; Ergolines; Gerbillinae; Male; Mice; Mice, Inbred Strains; Nicergoline; Rats; Rats, Inbred Strains; Vinca Alkaloids; Vincamine

The synaptosomal fraction obtained from the motor area of the cerebral cortex of normocapnic, normoxic or hypoxic "young adult," "mature" and "senescent" beagle dogs is incubated and analyzed for : ATP, ADP, AMP, creatine phosphate, pyruvate and lactate. The data are compared with those obtained from the whole controlateral cortical motor area, by the surface freezing technique. After hypoxic hypoxia /15 min; PaO2 = 17-19 mm Hg), the metabolite contents and ratios are differently affected by ageing when the evaluations are performed in the incubated synaptosomal preparation or in the controlateral whole cerebral tissue. In fact, ageing does not affect so much the cerebral changes that occur in the overall energetic state during the hypoxic assault in vivo, but rather those that the synaptosomes remember the tend to reverse during the subsequent incubation in vitro. The protective action of several drugs on the synaptosomal phosphorylation state is tested. Phenobarbital shows a quite broad, age-independent spectrum of action. (-)Eburnamonine and dihydroergocristine exhibits a more limited, age-dependent effectiveness, but are devoid of anesthetic action. Papaverine proves unable to affect the tested biochemical parameters.

Topics: Adenine Nucleotides; Aging; Animals; Dihydroergotoxine; Dogs; Female; Hypoxia; Lactates; Lactic Acid; Motor Cortex; Phenobarbital; Phosphocreatine; Pyruvates; Pyruvic Acid; Synaptosomes; Vinca Alkaloids

Topics: Age Factors; Aging; Animals; Brain; Cytidine Diphosphate Choline; Dihydroergotoxine; Male; Nicergoline; Papaverine; Rats; Suloctidil; Theophylline; Trimetazidine; Vinca Alkaloids; Vincamine