The brains of morphine dependent rats were explored for areas sensitive to naloxone precipitated withdrawal. Stainless steel guide cannulas were implanted into different brain areas of male albino rats. One to 5 days after cannula implantation, physical dependence on morphine was induced by s.c. implantation of a pellet containing 75 mg of morphine base. Naloxone hydrochloride crystals were intracerebrally applied 70 to 76 hr after morphine pellet implantation. After application of naloxone, the abstinence signs of wet shakes and escape behavior were most frequently elicited in the medial thalamus and in medial areas of the diencephalic mesencephalic junctures. Neocortical, hippocampal, hypothalamic, tegmental, lateral thalamic and striatal areas of the brain were less sensitive to naloxone precipitated withdrawal. The neuroanatomical pathways related to opioid dependence are discussed.
|Original language||English (US)|
|Number of pages||8|
|Journal||Journal of Pharmacology and Experimental Therapeutics|
|State||Published - Dec 1 1973|