Partial depletion of endogenous zinc level by (D-Pen2, D-Pen5)enkephalin in the rat brain.
The effects of the potent delta opioid agonist (D-Pen2, D-Pen5)enkephalin (DPDPE) were studied on the endogenous levels and regional distribution of Zn2+ in rat central nervous system by means of flame atomic absorption spectrophotometry. The olfactory bulb exhibited the highest Zn2+ level, followed by the frontal and parietal cortices, striatum and hippocampus; the lowest ion levels were found in the medulla and thoracic spinal cord. Intracerebroventricular administration of DPDPE resulted in significant, time- and dose-dependent decreases in endogenous Zn2+ contents in the parietal cortex, hippocampus and striatum. The action of DPDPE was antagonized by a 30 min naloxone pretreatment. Naloxone alone was without effect in eliciting these responses. Thus, delta opioid receptors may regulate or modulate endogenous Zn2+ levels in the rat brain.
Gulya
K
K
Central Research Laboratory, Albert Szent-Györgyi Medical University, Szeged, Hungary.
Kovács
G L
GL
Kása
P
P
D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D020881:Enkephalin, D-Penicillamine (2,5)-; D004745:Enkephalins / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006624:Hippocampus / Q000378:metabolism; D007276:Injections, Intraventricular; D009830:Olfactory Bulb / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000502:physiology; D017465:Receptors, Opioid, delta; D013997:Time Factors; D015032:Zinc / Q000378:metabolism*
D000700:Analgesics; D004745:Enkephalins; D011957:Receptors, Opioid; D017465:Receptors, Opioid, delta; D020881:Enkephalin, D-Penicillamine (2,5)-; D015032:Zinc