AN ADAPTATION OF THE PUSH‐PULL CANNULA METHOD TO STUDY THE IN VIVO RELEASE OF [3H]DOPAMINE SYNTHESIZED FROM [3H]TYROSINE IN THE CAT CAUDATE NUCLEUS: EFFECTS OF VARIOUS PHYSICAL AND PHARMACOLOGICAL TREATMENTS

作者：A. Nieoullon, A. Chéramy, Jacques Glowinski · 发表于：Journal of Neurochemistry · 年份：1977 · DOI：10.1111/j.1471-4159.1977.tb10633.x · 被引用次数：145 · 研究领域：Neurotransmitter Receptor Influence on Behavior、Neuroscience and Neuropharmacology Research、Neurological disorders and treatments

Abstract— The release of [3H]dopamine ([3H]DA) continuously synthesized from l‐[3,5–3H]tyrosine from the caudate nucleus of the cat was estimated in halothane anaesthetized or‘encéphale isolé’animals. For this purpose, an improved superfusion cannula, avoiding tissue damage, was used. The best localization for the tip of the superfusion cannula was found first by determining the topographical distribution of endogenous DA within the caudate nucleus. A rostro‐caudal heterogenous distribution of the transmitter was detected. In perfusion experiments, l‐[3,5–3H]tyrosine was introduced continuously at a rate of 33μl/min. [3H]DA was the only catecholamine found in serial 15 min fractions as revealed by cochromatography. The spontaneous release of [3H]DA was greater in anaesthetized than in ‘encéphale isolé’ cats; it represented 150 and 100 times the blank value, respectively. Depolarization by K+ (30 mm) applied locally in the striatum or by electrical or mechanical stimulation of the substantia nigra caused a transitory increase in [3H]DA release. Conversely, a decrease in nerve activity induced by tetrodotoxin (5 × 10−‐7 m) or by electrocoagulation of the substantia nigra was associated with a decline in the amounts of [3H]DA in superfusates. A temporary reduction in [3H]DA release could also be obtained by a short‐lasting cooling block of the substantia nigra. As expected, d‐amphetamine (10−‐5 m) and benzotropine(10−‐7 m) added to the superfusing medium increased [3H]DA release...