目的：此研究在於比較年輕（三個月）及年老（十四個月）雄性Wistar大鼠乳激素細胞內鈣離子反應。方法與結果：甲釋素刺激對細胞內鈣離子的反應可以分三種類型，A型細胞對低(1nM)、中(10nM)劑量釋素皆有反應；B型細胞對中(10nM)、高(100nM)劑量甲釋素皆有反應；C型細胞對僅對高(100nM)劑量甲釋素有反應。年輕大鼠泌乳激素細胞內鈣離子對甲釋素刺激反應的比率(75.4%)顯著地比年老大鼠低(67.5%)。雖然C型細胞在年輕大鼠顯著地比年老大鼠高（分別是45.4%和17.5%），而在B型細胞年老大鼠顯著地比年輕大鼠高（分別是30.7%和9.1%），而大年老大鼠細胞內鈣離子對中、低劑量皆敏者占較大的比率。結論：雖然泌乳激素細胞在老化過程中黑心移成對中、低劑量敏感弄的細胞，這些結果亦顯示在老化過程中增加對較低劉量敏感型的細胞可能代償對高劑量甲釋素刺激有反應的泌乳激素細胞的降低。
Purpose: To compare intracellular Ca(superscript 2+) response of lactotrophs to TRH in young (3 months) and older (14months) male Wistar rats. Methods and results: We found three types of intracellular Ca(superscript 2+) responses to TRH stimulation. Type A was sensitive to 1 nM, 10 nM TRH. We also found that a significantly great percentage of young rats had intracellular Ca(superscript 2+) responses to TRH stimulation than the old rats (75.4% and 67.5%, respectively). The young rats had a significantly greater percentage of Type A responses than the old rats (45.5%vs. 17.5%), whereas the older rats had a significantly greater percentage of Type B responses than the young ones(30.7%vs.9.1%), There was no significant difference between the two groups with regard to Type C responses (20.1%vs.20.3%). Moreover, the intracellular Ca(superscript 2+) response in the medium and low sensitive cells became higher in the older rats. Conclusion: Although the high-sensitive lactotrophs become medium and low-sensitive cell types during the aging process, increases in intracellular Ca(superscript 2+) response to TRH stimulation in cell types with lower sensitivities may compensate for the decreases in aging.
