Participation of Endogenous Opioid Peptide in Sudden Death

以Wistar大鼠为实验对象，采用放射免疫法测定大鼠死后脑垂体免疫反应性β-内啡肽(IR-β-EP)水平的变化，以及痛苦时循环血中IR-β-EP水平的变化，观察大鼠分别静脉注射KCl和SCC所致心力衰竭和呼吸衰竭型(CFT)和呼吸衰竭(RFT)猝死的反应。在器官重量与体重之比有显著差异的雌雄垂体腺(CFT&GT；RFT)中，RFT组的IR-β-EP显著低于CFT组(P<0.05)。CFT组大鼠短期疼痛时血浆IR-β-EP无明显变化，而RFT组大鼠长期疼痛时血浆IR-β-EP显著升高。男性在SCC给药后2或4分钟最高升高值约为给药前的3倍(P0.01)。但女性的海拔高度低于男性。RFT疼痛时血浆IR-β-EP升高被认为是…地塞米松治疗导致更多的脑垂体源性疾病。因此，我们得出结论，与CFT相比，RFT的垂体会对致命的痛苦做出更多的反应。我们试图用相同品系的大鼠来确定β-内啡肽(β-EP)对呼吸系统和心血管系统影响的性别差异。正常雌雄大鼠脑室注射β-EP(0.18 mg/kg)后，呼吸频率(RR)、心率(HR)和平均动脉压(MABP)均显著降低(P0.01或0.001)，呼出气中CO2显著升高(P0.01)。这种抑制作用可被静脉注射纳洛酮(0.2 mg/kg)一过性阻断。发情和发情雌性大鼠之间的β-EP的作用没有发现差异。女性对RR、HR和平均动脉压的影响明显强于男性(0.001·05，P<0·05)。去的大鼠表现出与正常雌性相同的抑制作用，但过度切除的大鼠的抑制作用与正常雌性没有区别。在睾丸切除和卵巢切除用睾酮治疗的大鼠中，前者显示出与完整雄性相同的结果，但后者不同。因此，雄激素能显著减轻β-EP对雄性大鼠呼吸系统和心血管系统的抑制作用。较少

Using male and female Wistar rats, pituitary response to cardiac and respiratory failure type (CFT and RFT) sudden death caused by the intravenous administration of KCl and SCC, respectively, was examined by analyzing variation in pituitary immunoreactive beta-endorphin (IR-beta-EP) levels determined by radioimmunoassay after death and in circulating IR-beta-EP levels during periods of agony. In the pituitary gland of both sexes which differed significantly in ratio of the organ weight to body weight for CFT and RFT (CFT>RFT), IR-beta-EP was significantly less in RFT than in CFT (P 0.05). No variation in plasma IR-beta-EP was noted during short periods of agony in CFT, but it markedly increased during long periods of agony in RFT. The highest elevation at 2 or 4 minutes after SCC administration was about 3 times the preadministration value for IR-beta-EP in males (P 0.01). But elevation in females was lower than in males. Rise in plasma IR-beta-EP during agony of RFT is regarded to be … More of pituitaryorigin due to dexamethasone treatment. The pituitary was thus concluded to respond more to the fatal agony in RFT than in CFT.An attempt was made to determine sex differences in the effects of beta-endorphin ( beta-EP) on respiratory and cardiovascular systems using the same strain rats. By the intracerebroventicular administration of beta-EP (0.18 mg/kg) to normal male and female rats, respiratory rate (RR), heart rate (HR) and mean arterial blood pressure (MABP) were depressed significantly (P 0.01 or 0.001) and CO_2 in expired gas increased significantly (P 0.01). These suppressive effects of the peptide were transiently blocked by the intravenous injection of naloxone (0.2 mg/kg). No differences in the effects of beta-EP between estrous and diestrous female rats could be detected. The effects of the peptide were significantly stronger in RR, HR and MABP for females than for males (0.001 P 0.05). Testectomized rats showed suppressive effects of the peptide to the same extent as intact females, but the effects in overiectomized rats did not differ from those for intact females. In testectomized and ovariectomized rats treated with testosterone, the former showed the same results as intact males, but not the latter. The suppressive effects of beta-EP on the respiratory and cardiovascular systems are thus remarkably relieved by androgen in male rats. Less