| 摘要: | 嬰兒點頭痙攣(IS)是嬰兒時期特有的一種癲癇疾病。病嬰對一般抗痙攣藥物治療效應較差
，然而對投與促腎上腺皮質素(ACTH)或類固醇的治療有明顯較佳的效果。ACTH的分泌主要
是受到下視丘的親皮質素釋放激素(CRH)的調控，且已證實CRH此神經荷爾蒙(neurohormon
e)在人類幼年癲癇或幼鼠痙攣的發生扮有相當重要的角色。因而有學者提出「CRH的過量
產生導致IS發生」之假說，此外在動物實驗方面，於幼鼠腦室注射CRH比起成鼠能更快速
的引起痙攣。近年來許多研究發現細胞激素具有調節內分泌的功能，並參與許多中樞神經
系統疾病的過程進展。基於以上原因，為更深入了解CRH在癲癇所參與的病理機轉，我們
測量IS病人其周邊血液CRH濃度的變化是否和IS有關？或在以紅藻胺酸(KA)引發癲癇的出
生後7天、14天、30天老鼠其抽搐程度的加重是否能使CRH和細胞激素(IL-1(, IL-6, TNF-
()在周邊或腦中表現增加？實驗結果指出，不論是IS病人血漿中CRH濃度(0.546(0.184 ng
/ml, n=12, p<0.001)或是年齡相符的一般癲癇病人(0.294(0.032 ng/ml, n=13, p<0.01)
都較控制組病人(0.135(0.022 ng/ml, n=12)為高。在注射KA後3小時的出生30天老鼠(P30
)其血中CRH濃度(0.368(0.06 ng/ml, n=4, p<0.05)明顯較控制組為高；但在注射KA後1小
時的P14天老鼠其血中CRH濃度(0.260(0.04 ng/ml, n=6)和控制組比起則無統計上的差異
。此外以反轉錄聚合脢連鎖反應方法半定量測量到CRH mRNA在P7、P14天注射KA老鼠的大
腦皮質部位之表現量分別較控制組增加了7.84倍及1.55倍；另外IL-1(、IL-6、TNF-( mRN
A也在P7天注射KA老鼠的大腦皮質部位增加表現量。以上結果顯示支持CRH的過度產生和IS
有極大的相關，並推測在腦部發育過程中CRH可能是一個致痙攣前驅物(pro-convulsant)
，而因癲癇所導致CRH在大腦皮質的表現增加，進而活化細胞激素可能導致腦部不正常之
過度興奮現象而對癲癇程度的進展極為重要。
Infantile spasm (IS), is a form of epilepsy specifically occurring at infant s
tage, is refractory to conventional anticonvulsant treatment but is exceptiona
lly sensitive to adrenocorticotropic hormone (ACTH) treatment. Corticotropin-
releasing hormone (CRH), a major regulatory factor of ACTH secretion in pituit
ary, has been implicated as an important neuro-hormone participating in seizur
e generation particularly in early life of both human and animals. In human,
excessive production of CRH is speculated as one of the pathological mechanism
s underlying the generation of IS. In animal, intracerebral injection of CRH
potently produces seizure behavior since early life. Recently, cytokines also
participated in communication between immunity and central nerve system disea
ses. To further understand the role of CRH in pathological mechanisms of seiz
ure, we investigated whether increased plasma CRH level is associated with IS
and whether seizure activity will increase the expression of CRH and cytokines
(IL-1(, IL-6 and TNF-() in circulation and in brain of neonatal rats. Plasma
CRH level in IS patients (0.546(0.184 ng/ml, n=12, P<0.001) or seizure patien
ts (0.294(0.032 ng/ml, n=13, P<0.01) is significantly higher as compared to co
ntrol (0.135(0.022 ng/ml, n=12). The plasma CRH level of postnatal 30-day (P3
0) rats at 3h after kainate (KA)-injection (0.368(0.06 ng/ml, n=4) is signific
antly higher (p<0.05) than that of control, whereas, plasma CRH level show no
statistically difference in P14 rats at 1h after KA-injection (0.260(0.04 ng/m
l, n=6) when compare to that of control. Furthermore, an 7.84 and 1.55 fold i
ncreased expression of CRH mRNA in cortex was observed in P7 and P14 rats with
KA-induced seizure by RT-PCR analysis. In addition, IL-1(, IL-6 and TNF-( mR
NA expression were increased in cortex of P7 rats with KA-induced seizure. The
se data support the hypothesis that over-production of CRH is likely associate
d with IS, and seizure activity induced by KA may also upregulate the CRH and
cytokines expression in neonatal developing brain. Given that CRH is a pro-co
nvulsant in developing brain, increase of CRH in cortex elicited by seizure ma
y further potentiate the progression of the activity of seizure. |
