Faculty Bibliography

Lateral ventricular injection of antibodies to dynorphin A(1-13) was previously shown to elevate lateral hypothalamic stimulation frequency threshold for eliciting feeding behavior. The antibodies utilized in that study cross-react completely with dynorphin A(1-17) and, to a lesser extent, dynorphin A(1-8). In the present study, highly specific antibodies to dynorphin A(1-17) and dynorphin A(1-8) were infused into the lateral ventricle and mesopontine aqueduct to determine which biologically active dynorphin A fragment mediates feeding and at what level of the CNS this activity is likely to occur. Both antibodies were found to elevate the feeding threshold. Dynorphin A(1-8) antibodies were effective at both injection sites while dynorphin A(1-17) antibodies were only effective at the lateral ventricular site. These findings suggest that feeding-related dynorphin A(1-17) activity may occur predominantly within the forebrain, while dynorphin A(1-8) activity occurs within the brainstem. Only the dynorphin A(1-8) antibodies, infused into the aqueduct, produced a naloxone-like pattern of progressive elevation in serially determined thresholds; this pattern was previously interpreted to reflect a reduction in consummatory reward. Dynorphin A(1-8) activity within some brainstem structure(s) may therefore contribute prominently to the opioid mechanism whose mediation of the hedonic response to food was previously inferred from naloxone antagonism.

In an open study, seven patients with Parkinson's disease received ECT for major depression. Both the motor dysfunction and the mood impairment of these patients improved following an average of seven ECT sessions. Significant improvement in motor function occurred after only two treatments. All aspects of Parkinson's disease improved significantly after ECT. Older patients showed greater improvement in motor function. The authors conclude that the therapeutic utility of ECT in depressed and nondepressed patients with Parkinson's disease should be further evaluated