ラットにおける放射線および熱傷複合損傷後の腸管粘膜の血流ボリュームおよびバリア機能に及ぼす頸部交感神経ブロックの影響

[Influence of cervical sympathetic nerve block on blood flow volume and barrier function of intestinal mucosa after combined radiation and burn injury in rat].

抄録

目的:

ラットにおける放射線および熱傷の複合障害後の腸管粘膜の血流およびバリア機能に及ぼす頸部交感神経ブロックの影響を検討する。

OBJECTIVE: To investigate the influence of cervical sympathetic nerve block (SB) on blood flow volume and barrier function of intestinal mucosa after combined radiation and burn injury in rat.

方法:

SDラットを3群に分けた：コントロール（n = 18）、複合損傷群（n = 100、線量5 GyのCoガンマ線体内照射と15％TBSAの全層熱傷のラット）、SB治療による複合損傷（n = 100、同量のガンマ線照射と熱傷を行い、SBで治療したラット）。複合傷害後0、1、5、7日目に20匹のラットを犠牲にし、種々の観察を行った。SB群ではropivhydrochlorideを両側の頸部に注射してSBを行い、複合損傷群では代わりに同量の普通生理食塩水を注射した。血流量、空腸の絨毛高さと陰窩深さの変化、Na(+)-K+ ATPase活性、小腸の透過性を各時点で測定した。

METHODS: SD rats were divided into three groups: control (n = 18), combined injury group (n = 100, rats with Co gamma ray body irradiation with a dose of 5 Gy plus 15% TBSA full-thickness burn injury), and combined injury with SB treatment (n = 100, with the same dose of gamma-ray irradiation and burn injury, treated with SB). Twenty rats were sacrificed on 0, 1, 5, 7 days after combined injuries for various observations. SB was conducted with injection of ropivhydrochloride into the neck bilaterally for the SB group, and same amount of normal saline was injected instead in the combined injury group. Blood flow volume, changes in villus height and crypt depth in jejunum, Na(+)-K+ ATPase activity, permeability of small intestine were measured at different time-points.

結果:

損傷後1日目の小腸粘膜の血流量は、正常対照群（1.26 +/- 0.23 ml x min(-1) x g(-1), P < 0.01 ）より明らかに減少し、pit細胞の破壊、腸粘膜Na(+)-K+ ATPase活性の低下および腸粘膜透過性の上昇がみられた。複合損傷群と比較すると、複合損傷1日後の血流量は［(0.82 +/- 0.11) ml x min(-1) x g(-1), P < 0.01］ であり、Na(+)-K+ ATPase活性は明らかに上昇し、小腸の透過性は改善された。

RESULTS: The blood flow volume in small intestinal mucosal on 1 post-injury days (PID) [(0.29 +/- 0.07) ml x min(-1) x g(-1)] were obviously decreased than that in normal controls [(1.26 +/- 0.23) ml x min(-1) x g(-1), P < 0.01 ], with serious destruction of pit cells, decrease in intestinal mucosal Na(+)-K+ ATPase activity, and increase in intestinal mucosal permeability. Compared with combined injury group, the blood flow volume was [(0.82 +/- 0.11) ml x min(-1) x g(-1) 1 day after combined injury, P < 0.01], and the Na(+)-K+ ATPase activity was obviously increased, and the permeability of small intestine was ameliorated.

結論:

SBは、放射線および熱傷の複合損傷後のラット小腸の血流量を増加させ、腸管上皮の修復を促進し、腸管壁のバリア機能を向上させることができる。

CONCLUSION: SB can increase blood flow volume of rat small intestine after combined radiation and burn injury, promote the repair of intestinal epithelium and improve the barrier function of the intestinal wall.