Effect of antiphlogistics on blood-brain barrier in lymphostatic encephalopathic and in normal rats

Abstract

Injection of the tremorigenic alkaloid harmine into lymphostatic encephalopathic rats leads to a longer duration of tremor and higher brain concentrations than in sham-operated controls. In lymphostatic encephalopathic as well as in normal rats different antiphlogistics shorten the tremor duration and decrease harmine concentration in brain. The antiphlogistics do not influence the plasma concentration of harmine, its protein binding and its tremorend concentration in brain. The effect of antiphlogistics in lymphostatic encephalopathic rats is considered as a consequence of the reduced blood-brain barrier permeability. Obviously in sick animals the blood-brain barrier permeability for harmine is not increased; the prolonged harmine tremor and the increased alkaloid concentration in the brain are consequences of the impaired cerebral lymphatic drainage only.

Influence of Surgical Manipulations on Hexobarbital Effects in Rats

“…There are also pharmacological consequences, e.g., in lymphostatic encephalopathic rats the duration of the harmine-induced tremor is prolonged due to an impaired lymphatic elimination of the alkaloid from brain. In our previous studies, harmine was used as a suitable probe which permitted an exact determi nation of both tissue concentration and tremor duration (Back and Seidel, 1975;Zetler et al, 1974).The question then arose whether, in rats with lymphostatic encephalopathy, the effects of other centrally acting drugs are changed in parallel to those of harmine. Therefore, hexobarbital was administered to lymphostatic encephalopathic, as well as to sham-operated rats.…”