- J. Jordan
- Clinical Autonomic Research
- Clin Auton Res 16 (6): 360-362
Several previous studies suggested that agonistic antibodies directed against g-protein coupled receptors may contribute to human cardiovascular disease. A new study suggests that agonistic beta-adrenoreceptor antibodies may contribute to sinus tachycardia. In that study, more than 50% of patients with inappropriate sinus tachycardia tested positive for the antibody. The antibody was not detected in any of the control subjects. Further studies are needed to demonstrate the functional relevance of agonistic beta-adrenoreceptor antibodies in vivo. Another study determined the effect of magnesium sulfate treatment in patients with severe tetanus. The desired outcome was that magnesium sulfate might decrease the need for mechanical ventilation, which was unfortunately not the case. However, compared to placebo, magnesium reduced the requirement for skeletal muscle relaxants and sedatives. Furthermore, magnesium treatment attenuated episodes of sinus tachycardia reflecting autonomic instability. Thus, magnesium sulfate appears to be a useful and inexpensive adjunctive treatment for autonomic instability patients affected by tetanus. Finally, a study in rainbow trout suggests that spontaneous baroreflex sensitivity can be determined in fish. Fish may serve as another important model for baroreflex research.