Sagvolden T, Hendley E D, Knardahl S
Department of Neurophysiology, University of Oslo, Norway.
Physiol Behav. 1992 Jul;52(1):49-57. doi: 10.1016/0031-9384(92)90432-2.
The spontaneously hypertensive rat (SHR) is behaviorally hyperactive relative to the Wistar-Kyoto rat (WKY). By breeding SHR with WKY, followed by inbreeding, two new strains have been developed in which hypertension seems to be separated from hyperactivity to novel stimuli: the WKHT and the WKHA strains. The main purpose of the present study was to determine which behavioral characteristics of SHR have been dissociated from the hypertensive trait in the WKHA strain. Male SHR, WKY, WKHT, and WKHA were subjected to three protocols: 1) Two forced-exploration tests, where the results showed that both the SHR and the WKHA rats were hyperactive. 2) A free-exploration open field, where the SHR was more active than the other strains, showing shorter latencies to leave the home cage, spending more time in the field, ambulating and rearing more. Furthermore, the WKHT behavior was more similar to the SHR behavior than the WKHA behavior. 3) A two-component schedule of reinforcement, where one component (fixed-interval 2 min) was signaled by houselight on and the other (extinction, EXT) by houselight off. In this test, the SHR behavior was markedly different from that of the three other strains: the fixed-interval scallop, the accelerated responding towards the end of the interval, was steeper in SHR than in the other groups. The SHR emitted more responses during the extinction component of the schedule. The SHR hyperactivity was dependent upon the reinforcement value of the water deliveries and was increased even further by sensory-reinforcing respones feedback lights. Thus, the hyperactivity of the WKHA strain seems to be less pervasive than that of the SHR.(ABSTRACT TRUNCATED AT 250 WORDS)
自发性高血压大鼠(SHR)相对于Wistar-Kyoto大鼠(WKY)在行为上表现为多动。通过将SHR与WKY杂交,然后进行近亲繁殖,培育出了两个新的品系,其中高血压似乎与对新刺激的多动分离:WKHT和WKHA品系。本研究的主要目的是确定SHR的哪些行为特征在WKHA品系中已与高血压性状分离。雄性SHR、WKY、WKHT和WKHA接受了三个实验方案:1)两个强迫探索测试,结果显示SHR和WKHA大鼠均表现为多动。2)一个自由探索旷场实验,SHR比其他品系更活跃,表现出离开家笼的潜伏期更短,在旷场中停留的时间更长,走动和竖毛更多。此外,WKHT的行为比WKHA的行为更类似于SHR的行为。3)一个双成分强化程序,其中一个成分(固定间隔2分钟)由房灯亮起信号表示,另一个成分(消退,EXT)由房灯熄灭信号表示。在这个测试中,SHR的行为与其他三个品系明显不同:固定间隔扇贝形曲线,即在间隔结束时加速反应,在SHR中比在其他组中更陡峭。SHR在程序的消退成分中发出更多反应。SHR的多动取决于水递送的强化值,并且通过感觉强化反应反馈灯进一步增加。因此,WKHA品系的多动似乎不如SHR普遍。(摘要截断于250字)