BACKGROUND Lung transplantation is a well-established treatment of end-stage lung disease.A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation.However,masterin...BACKGROUND Lung transplantation is a well-established treatment of end-stage lung disease.A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation.However,mastering the surgical technique takes time owing to the small organ size.AIM To conduct rat lung transplantation using a shunt cannula(SC)or modified cannula(MC)and assess their efficacy.METHODS Rat lung transplantation was performed in 11 animals in the SC group and 12 in the MC group.We devised a method of rat lung transplantation using a coronary SC for coronary artery bypass surgery as an anastomosis of pulmonary arteri-ovenous vessels and bronchioles.The same surgeon performed all surgical proce-dures in the donor and recipient rats without using a magnifying glass.The success rate of lung transplantation,operating time,and PaO2 values were com-pared after 2-h reperfusion after transplantation.RESULTS Ten and 12 lungs were successfully transplanted in the SC and MC groups,respectively.In the SC group,one animal had cardiac arrest within 1 h after reperfusion owing to bleeding during pulmonary vein anastomosis.The opera-ting time for the removal of the heart-lung block from the donor and preparation of the left lung graft was 26.8±2.3 and 25.7±1.3 min in the SC and MC groups,respectively(P=0.21).The time required for left lung transplantation in the recipients was 37.5±2.8 min and 35.9±1.4 min in the SC and MC groups,respectively(P=0.12).PaO2 values at 2 h after reperfusion were 456.2±25.5 and INTRODUCTION Lung transplantation is a well-established treatment of end-stage lung disease.Many immune and non-immune mech-anisms in lung transplantation are highly complex,and post-transplant complications such as infections and primary and chronic lung allograft dysfunction must be reduced to improve survival.Therefore,there is a need for immunological and pathophysiological analyses using animal lung transplantation models.The rat lung transplantation model was first reported in 1971[1],followed by the Mizuta Cuff model[2]in 1989.Since then,various improvements in surgical techniques,cuffs,and instruments have been reported[3-7].The advantage of using a rodent model is that it permits inexpensive collection of biological data from a living model after lung transplantation.Although trained surgeons can perform the transplantation procedure,mastering the surgical technique takes time due to the small size of the organs.The risks associated with this technique include damage to the vulnerable pulmonary artery(PA)and pulmonary vein(PV)vessel walls during anastomosis,as well as stenosis of the anastomotic site.We developed an anastomotic technique using a coronary shunt cannula(SC)for cardiac coronary artery bypass surgery as an alternative to the previously reported cuff method[2-6].This method enables anastomosis by inserting and ligating a cannula into the lumen of the PA,PV,and bronchus(Br),which is simpler and more reliable than conventional methods.This study aimed to determine problems with rat lung transplantation using the SC,develop an improved cannula,and investigate its utility.RESULTS After creating 11 lung transplantation model animals in the SC group and 12 in the MC group,all animals underwent reperfusion.One animal in the SC group had cardiac arrest 1 h after reperfusion due to hemorrhage caused by vessel wall injury during PV anastomosis.Two hours after reperfusion,we visually confirmed the maintenance of recipient hemody-namics and blood flow in the graft pulmonary cannula in 10 animals in the SC group and 12 in the MC group.The operating time for the removal of the heart-lung block from the donor and graft lung creation was 26.8±2.3 min in the SC group and 25.7±1.3 min in the MC group(P=0.21,Table 1).The duration for left lung transplantation into the recipient was 37.5±2.8 min in the SC group and 35.9±1.4 min(P=0.12,Table 1)in the MC group.Although no significant difference was found between the SC and MC groups,animals in the MC group experienced a slightly shorter operating time,smoother surgical technique,and less stressful procedure for the surgeons compared with those in the SC group.The graft lung coloration(Grade 1/2/3)after reperfusion was 0/2/8(SC group)and 0/2/10(MC group),and all grafts were reported to be successful,except in one animal in the SC group that had cardiac arrest(Table 2).The PaO2 values after 2 h of reperfusion were 456.2±25.5 mmHg in the SC group and 461.2±21.5 mmHg in the MC group(P=0.63,Table 3),showing no significant difference between the groups.展开更多
Vascular formation in vivo involves several processes and signal cascades subsequently occurring in the embryo. Several models by ES cells have been reported for analysis in vitro. We show here a 3D culture system usi...Vascular formation in vivo involves several processes and signal cascades subsequently occurring in the embryo. Several models by ES cells have been reported for analysis in vitro. We show here a 3D culture system using collagen gel (AteloCell) as a simple and useful system for investigating vascular formations and analyzing the roles of factors in vivo. Although VEGF and PDGF are growth factors with multi-potentials for vascular formation, their sequential roles have not been elucidated. We investigated the effects of VEGF and PDGF B signals for vascular formation by a 3D culture system that embedded embryoid bodies (EBs) from ES cells into a collagen gel. After embedding EBs in the collagen gel with a medium containing VEGF, EBs gave off CD105 immunopositive vessels as the initial step of vasculogenesis. When the factor in the culture medium for EBs was switched from VEGF to PDGF B after 5 days of culture, the morphological features of vessels varied, suggesting the occurrence of vascular-type differentiation. After 11 days of 3D culture, vessels in both groups cultured with VEGF alone and switching to VEGF B at day 5 showed Flk-1 immunoreactivity. Some blood vessels cultured with PDGF B after day 5 expressed either EphrinB2 (arteriole marker) or Flt-4 (lymphatic marker) immunoreactivity, but vessels cultured with VEGF alone exhibited neither of them. Vessels cultured with these two factors could not differentiate into a venous type. The present study indicates that VEGF is the initial signal for vasculogenesis, and that PDGF B is probably involved in vascular diversification.展开更多
文摘BACKGROUND Lung transplantation is a well-established treatment of end-stage lung disease.A rodent model is an inexpensive way to collect biological data from a living model after lung transplantation.However,mastering the surgical technique takes time owing to the small organ size.AIM To conduct rat lung transplantation using a shunt cannula(SC)or modified cannula(MC)and assess their efficacy.METHODS Rat lung transplantation was performed in 11 animals in the SC group and 12 in the MC group.We devised a method of rat lung transplantation using a coronary SC for coronary artery bypass surgery as an anastomosis of pulmonary arteri-ovenous vessels and bronchioles.The same surgeon performed all surgical proce-dures in the donor and recipient rats without using a magnifying glass.The success rate of lung transplantation,operating time,and PaO2 values were com-pared after 2-h reperfusion after transplantation.RESULTS Ten and 12 lungs were successfully transplanted in the SC and MC groups,respectively.In the SC group,one animal had cardiac arrest within 1 h after reperfusion owing to bleeding during pulmonary vein anastomosis.The opera-ting time for the removal of the heart-lung block from the donor and preparation of the left lung graft was 26.8±2.3 and 25.7±1.3 min in the SC and MC groups,respectively(P=0.21).The time required for left lung transplantation in the recipients was 37.5±2.8 min and 35.9±1.4 min in the SC and MC groups,respectively(P=0.12).PaO2 values at 2 h after reperfusion were 456.2±25.5 and INTRODUCTION Lung transplantation is a well-established treatment of end-stage lung disease.Many immune and non-immune mech-anisms in lung transplantation are highly complex,and post-transplant complications such as infections and primary and chronic lung allograft dysfunction must be reduced to improve survival.Therefore,there is a need for immunological and pathophysiological analyses using animal lung transplantation models.The rat lung transplantation model was first reported in 1971[1],followed by the Mizuta Cuff model[2]in 1989.Since then,various improvements in surgical techniques,cuffs,and instruments have been reported[3-7].The advantage of using a rodent model is that it permits inexpensive collection of biological data from a living model after lung transplantation.Although trained surgeons can perform the transplantation procedure,mastering the surgical technique takes time due to the small size of the organs.The risks associated with this technique include damage to the vulnerable pulmonary artery(PA)and pulmonary vein(PV)vessel walls during anastomosis,as well as stenosis of the anastomotic site.We developed an anastomotic technique using a coronary shunt cannula(SC)for cardiac coronary artery bypass surgery as an alternative to the previously reported cuff method[2-6].This method enables anastomosis by inserting and ligating a cannula into the lumen of the PA,PV,and bronchus(Br),which is simpler and more reliable than conventional methods.This study aimed to determine problems with rat lung transplantation using the SC,develop an improved cannula,and investigate its utility.RESULTS After creating 11 lung transplantation model animals in the SC group and 12 in the MC group,all animals underwent reperfusion.One animal in the SC group had cardiac arrest 1 h after reperfusion due to hemorrhage caused by vessel wall injury during PV anastomosis.Two hours after reperfusion,we visually confirmed the maintenance of recipient hemody-namics and blood flow in the graft pulmonary cannula in 10 animals in the SC group and 12 in the MC group.The operating time for the removal of the heart-lung block from the donor and graft lung creation was 26.8±2.3 min in the SC group and 25.7±1.3 min in the MC group(P=0.21,Table 1).The duration for left lung transplantation into the recipient was 37.5±2.8 min in the SC group and 35.9±1.4 min(P=0.12,Table 1)in the MC group.Although no significant difference was found between the SC and MC groups,animals in the MC group experienced a slightly shorter operating time,smoother surgical technique,and less stressful procedure for the surgeons compared with those in the SC group.The graft lung coloration(Grade 1/2/3)after reperfusion was 0/2/8(SC group)and 0/2/10(MC group),and all grafts were reported to be successful,except in one animal in the SC group that had cardiac arrest(Table 2).The PaO2 values after 2 h of reperfusion were 456.2±25.5 mmHg in the SC group and 461.2±21.5 mmHg in the MC group(P=0.63,Table 3),showing no significant difference between the groups.
文摘Vascular formation in vivo involves several processes and signal cascades subsequently occurring in the embryo. Several models by ES cells have been reported for analysis in vitro. We show here a 3D culture system using collagen gel (AteloCell) as a simple and useful system for investigating vascular formations and analyzing the roles of factors in vivo. Although VEGF and PDGF are growth factors with multi-potentials for vascular formation, their sequential roles have not been elucidated. We investigated the effects of VEGF and PDGF B signals for vascular formation by a 3D culture system that embedded embryoid bodies (EBs) from ES cells into a collagen gel. After embedding EBs in the collagen gel with a medium containing VEGF, EBs gave off CD105 immunopositive vessels as the initial step of vasculogenesis. When the factor in the culture medium for EBs was switched from VEGF to PDGF B after 5 days of culture, the morphological features of vessels varied, suggesting the occurrence of vascular-type differentiation. After 11 days of 3D culture, vessels in both groups cultured with VEGF alone and switching to VEGF B at day 5 showed Flk-1 immunoreactivity. Some blood vessels cultured with PDGF B after day 5 expressed either EphrinB2 (arteriole marker) or Flt-4 (lymphatic marker) immunoreactivity, but vessels cultured with VEGF alone exhibited neither of them. Vessels cultured with these two factors could not differentiate into a venous type. The present study indicates that VEGF is the initial signal for vasculogenesis, and that PDGF B is probably involved in vascular diversification.
