Hypothalamic sensitivity to leukocytic pyrogen of adult and new‐born guinea‐pigs.
Hypothalamic sensitivity to leukocytic pyrogen of adult and new‐born guinea‐pigs.
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成年和新生豚鼠的下丘脑对白细胞热原的敏感性。
DOI：
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发表时间：
1979
期刊：
影响因子：
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通讯作者：
K. A. Smith
中科院分区：
文献类型：
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作者：
C. Blatteis;K. A. Smith
1.进行实验以定位显微注射白细胞热原的下丘脑作用部位，并比较该部位在成年和新生豚鼠中的致热敏感性。为了确定对白细胞热源有反应的部位，通过立体定位插管向清醒的成年豚鼠双侧（距离中线0.8 - 1.0 mm）注射1微升，插管以0.5 mm的间隔和从嗅盖到乳头体的不同深度进行定位。注射到视前区产生尖锐的双相热与短lavelus，而注射到circumjobalus网站诱发较小的发热与较长的lavelus。3.为了评估该部位热原敏感性的个体发生，将双侧注射1.00、0.50和0.25 μ L白细胞热原的发热反应与0至5天、6至12天和13至16天龄以及成年豚鼠进行了比较。新生豚鼠和成年豚鼠的最小致热原剂量为0.25 μ L，但对该剂量产生发热反应的0至5日龄动物数量较少且体重较大;“相对于年龄较小”的新生豚鼠体温过低。4.发热动物的数量随年龄增加而增加;在任何年龄，增加白细胞热原剂量也会增加发热动物的数量。5.这些结果表明，发热反应可能取决于热原接受机制的发展阶段。他们进一步暗示，白细胞热原的行为和热传入的整合可能是不一样的，因为体温调节能力是完全有能力从出生。
1. Experiments were conducted to localize the hypothalamic site of action of microinjected leucocytic pyrogen and to compare the pyrogenic sensitivity of this locus in adult and new‐born guinea‐pigs.2. To identify the site reactive to leucocytic pyrogen, bilateral (0.8‐1.0 mm from the mid line) injections of 1 microliter were made into conscious adult guinea‐pigs via cannulas stereotaxically palced at 0.5 mm intervals and varying depths from the olfactory tegmentum to the mammillary bodies. Injections into the preoptic area produced sharp monophasic fevers with short latencies, whereas injections into circumjacent sites evoked smaller fevers with longer latencies. 3. To assess the ontogeny of the pyrogenic sensitivity of this locus, the febrile response to 1.00, 0.50, and 0.25 microliter leucocytic pyrogen injected bilaterally was compared to 0 to 5‐, 6 to 12‐, and 13 to 16‐day old and in adult guinea‐pigs. The minimum pyrogenic dose in both new‐born and adult guinea‐pigs was 0.25 microliter, but the 0 to 5‐day old animals which responded with a fever to this dose were few in number and large in weight; ‘small‐for age’ neonates became hypothermic. 4. The number of febrile animals increased with age; it also could be increased by increasing the dose of leucocytic pyrogen at any age. 5. These results suggest that febrile responsiveness may depend on the stage of development of, presumably, the pyrogen‐receptive mechanism. They further imply that the preoptic sites where leucocytic pyrogen acts and thermoafferents are integrated may not be the same, since thermoregulatory capability is fully competent from birth.