豚鼠胎儿体外肺脏液体生成：精氨酸加压素和精氨酸催产素的作用

Lung liquid production by in vitro lungs from fetal guinea pigs: effects of arginine vasopressin and arginine vasotocin.

作者信息

Perks A M, Kindler P M, Marshall J, Woods B, Craddock M, Vonder Muhll I

机构信息

Department of Zoology, Obstetrics and Gynaecology, University of British Columbia, Vancouver, Canada.

出版信息

J Dev Physiol. 1993 May;19(5):203-12.

PMID:8083497

Abstract

Lungs from near-term fetal guinea pigs were supported in vitro for 3 h; lung liquid production rates were measured by a dye dilution technique. Seventy preparations were used to study the effects of arginine vasopressin (AVP) placed in the outer saline for the middle hour, at concentrations reported at birth [fetuses 61 +/- 2 days of gestation; 94.7 +/- 16.2 g (SD) body weight]. At 1200 microU/ml, AVP arrested fluid production (rates, successive hours, 3.03 +/- 0.60, 0.50 +/- 0.14 and 0.02 +/- 0.08 ml/kg body weight per h; falls significant, P < 0.01-0.0005). At 600, 300 and 100 microU/ml there were significant but smaller reductions. Reabsorptions were seen in 8 preparations given 600-1200 microU/ml, AVP. Preparations given 10 microU/ml AVP, AVP carrier or control saline showed no significant change. The responses (% reductions during treatment), were linearly related to the log concentration of AVP (r = 0.99); theoretical threshold, 8 microU/ml). Increasing treatment to 2h did not increase final responses. Preparations from 5 fetuses > 120 g body weight showed significantly greater responses (P < 0.025) [fetuses 64 +/- 2 days of gestation; 135.1 +/- 18.6 g (SD) body weight]. 10(-6) M amiloride abolished responses to AVP [fetuses 62 +/- 1 days of gestation; 93.4 +/- 18.5 g (SD) body weight, n = 30; rates, succeeding hours; AVP alone, 1.78 +/- 0.22, 0.48 +/- 0.09, 0.16 +/- 0.99 (P < 0.01-0.0005); AVP with amiloride, 1.15 +/- 0.07, 0.93 +/- 0.10, 0.86 +/- 0.08 (no significant fall) ml/kg body weight per h]. Thirty-six preparations treated with arginine vasotocin (AVT, 10-600 microU/ml) showed closely similar responses to those from AVP. These studies extend results to fetal guinea pigs, and show that AVP, at concentrations reported at delivery, can slow lung liquid production or cause reabsorption by a direct action on the lung. The effect increases close to term, and is due to activation of amiloride-sensitive Na+ channels.

摘要

将近足月豚鼠胎儿的肺在体外支持3小时；通过染料稀释技术测量肺液生成速率。使用70个标本研究在中间1小时置于外部盐溶液中的精氨酸加压素（AVP）的作用，浓度为出生时报道的浓度[妊娠61±2天的胎儿；体重94.7±16.2 g（标准差）]。在1200微单位/毫升时，AVP使液体生成停止（速率，连续小时数，分别为3.03±0.60、0.50±0.14和0.02±0.08毫升/千克体重每小时；下降显著，P<0.01 - 0.0005）。在600、300和100微单位/毫升时，有显著但较小的减少。在给予600 - 1200微单位/毫升AVP的8个标本中观察到重吸收。给予10微单位/毫升AVP、AVP载体或对照盐溶液的标本无显著变化。反应（治疗期间的减少百分比）与AVP的对数浓度呈线性相关（r = 0.99）；理论阈值为8微单位/毫升。将治疗时间延长至2小时并未增加最终反应。来自5个体重>120克胎儿的标本显示出显著更大的反应（P<0.025）[妊娠64±2天的胎儿；体重135.1±18.6 g（标准差）]。10⁻⁶M氨氯地平消除了对AVP的反应[妊娠62±1天的胎儿；体重93.4±18.5 g（标准差），n = 30；速率，后续小时数；单独使用AVP时，分别为1.78±0.22、0.48±0.09、0.16±0.99（P<0.01 - 0.0005）；AVP与氨氯地平联合使用时，分别为1.15±0.07、0.93±0.10、0.86±0.08（无显著下降）毫升/千克体重每小时]。用精氨酸催产素（AVT，10 - 600微单位/毫升）处理的36个标本显示出与AVP处理的标本非常相似的反应。这些研究将结果扩展到豚鼠胎儿，并表明分娩时报道浓度的AVP可通过对肺的直接作用减缓肺液生成或导致重吸收。这种作用在接近足月时增强，并且是由于氨氯地平敏感的Na⁺通道的激活。