Stress mechanism - an emerging role for furosemide

ABSTRACT

The beneficial effect of furosemide in emergency treatment of acute left ventricular failure starts immediately with the intravenous administration before the occurrence of diuresis. Pulmonary-systemic redistribution of blood volume had been suggested in relieving the left ventricular strain. A central mechanism for furosemide could be suggested because; recent data point to furosemide high specificity and selectivity in antagonizing cerebral GABA neurotransmission and a state of neurohumoral imbalance was suggested in these patients. So this study was conducted to evaluate the potential role of furosemide in the physiological stress mechanism. The effect of a single intraperitoneal dose of furosemide [4mg/kg. of body weight] was tested in a model of emotional stress induced by ultrasound noise, on rat behavioral activity, serum corticosterone level together with the volume of diuresis. Ultrasound noise exposure in a frequency range of 30,000 Hz to 65,000 Hz led to a significant limitation of its activity [freezing reaction]. Serum corticosterone level and behavioral activity are increased significantly in furosemide treated non-stressed and stressed rats compared with both control or stressed group. The increase was marked in furosemide treated-stressed rats. The increase in serum corticosterone and behavioral activity by furosemide in stressed rats indicate a transformation of the stress state from [freezing reaction] to a state of a [defense reaction]. In conclusion; furosemide stimulates the central stress mechanism. This stimulation may be in favor of rapid and potent beneficial effect of furosemide inrecovery of neurohumoral imbalance in stress conditions which probably mediates the pituitary hypothalamic axis