Doty R L, Li C, Bagla R, Huang W, Pfeiffer C, Brosvic G M, Risser J M
Smell and Taste Center, Hospital of the University of Pennsylvania, and Department of Otorhinolaryngology, Head and Neck Surgery, School of Medicine, Philadelphia 19104, USA.
Psychopharmacology (Berl). 1998 Mar;136(1):75-82. doi: 10.1007/s002130050541.
The purpose of this study was to determine the influence of the D1-selective partial agonist SKF 38393 on the odor detection performance of rats using high precision olfactometry and a go/no-go operant task. Previous studies have found that the D2 receptor partial agonist quinpirole decreases such performance, but the influences of D1 receptor activation are unknown. In experiment 1, such detection performance to the odorant ethyl acetate was enhanced by SKF 38393, relative to saline, in male rats at 7.5 and 10.0 mg/kg i.p. dose levels, but not at the lower doses of 1.0, 2.5, and 5.0 mg/kg. In experiment 2, this enhancement was replicated at the 7.5 and 10.0 mg/kg doses and was shown to occur at the 12.5 mg/kg dose as well. In experiment 3, similar enhancement was shown for the odorant eugenol in female rats at the 7.5, 10.0 and 12.5 mg/kg doses, suggesting this effect is neither sex-specific nor confined to the odorant ethyl acetate. In experiment 4, a 0.025 mg/kg dose of the D1 receptor antagonist SCH 23390 depressed the enhancement produced to ethyl acetate by 7.5 mg/kg SKF 38393 to control levels. Overall, these data demonstrate that, in contrast to quinpirole, SKF 38393 improves odor detection performance in the rat and that this phenomenon can be attenuated by the D1 receptor blocker SCH 23390.
本研究的目的是使用高精度嗅觉测定法和一种强制选择的操作性任务，来确定D1选择性部分激动剂SKF 38393对大鼠气味检测性能的影响。先前的研究发现，D2受体部分激动剂喹吡罗会降低这种性能，但D1受体激活的影响尚不清楚。在实验1中，相对于生理盐水，腹腔注射剂量为7.5和10.0mg/kg的SKF 38393可增强雄性大鼠对气味剂乙酸乙酯的检测性能，但在1.0、2.5和5.0mg/kg的较低剂量下则无此效果。在实验2中，在7.5和10.0mg/kg剂量下重复了这种增强作用，并且在12.5mg/kg剂量下也观察到了这种增强。在实验3中，雌性大鼠在7.5、10.0和12.5mg/kg剂量下对气味剂丁香酚也表现出类似的增强作用，这表明这种效应既不是性别特异性的，也不仅限于气味剂乙酸乙酯。在实验4中，0.025mg/kg剂量的D1受体拮抗剂SCH 23390将7.5mg/kg SKF 38393对乙酸乙酯产生的增强作用抑制到了对照水平。总体而言，这些数据表明，与喹吡罗相反，SKF 38393可改善大鼠的气味检测性能，并且这种现象可被D1受体阻滞剂SCH 23390减弱。
