TY - JOUR
T1 - Intestinal microvascular patterns during hemorrhagic shock
AU - Morini, Sergio
AU - Yacoub, Wael
AU - Rastellini, Cristiana
AU - Gaudio, Eugenio
AU - Watkins, Simon C.
AU - Cicalese, Luca
PY - 2000
Y1 - 2000
N2 - While injuries due to a hypoxic state commonly appear later in both intestinal crypts and basal portion of the villi than in the apical portion, a nonhomogeneous distribution of blood flow in the intestinal mucosa may be supposed. The presence of two different microvascular plexuses inside the mucosa, corresponding to the cryptal plexus and the villous plexus, supports the above hypothesis. This work studies the intestinal microvasculature in shocked versus normal rats. Forty-five rats were divided into four groups to study the histological damage and the microvascular bed by ink injection, fluorescent microsphere infusion, and resin injection for scanning electron microscopy (SEM) of vascular corrosion cast (VCC) observations. An infusion pressure of 100 ± 5 mm Hg was used in control animals, while 30 ± 5 mm Hg infusion pressure was adopted for controls as well as for shocked animals to simulate physiological or shock conditions. Hemorrhagic shock was induced by removing blood and maintaining a mean arterial pressure of 30 ± 5 mm Hg for 45-120 mins. A close connection among the patterns of microvasculature obtained with VCC and ink injection technique can be appreciated. In normal rats the whole microvasculature was visualized, but in both normal and shocked animals injected at low pressure different patterns could be found, generally showing a highly incomplete visualization of the vascular network. A significant decrease of visualization of both the entire microvasculature and the villous plexus is present in shocked animals when compared to unshocked controls, while no difference in the cryptal plexus visualization was observed. These observations suggest that the cryptal plexus is perfused preferentially during hemorrhagic shock, as a consequence of its peculiar microvascular organization. This may explain the relative resistance of the crypts, compared to villi, to hypoxic injuries in order to sustain endocrine function and the regenerative capability of the mucosa after prolonged hypoperfusion conditions that can lead to villous damage and temporary loss of the intestinal barrier function.
AB - While injuries due to a hypoxic state commonly appear later in both intestinal crypts and basal portion of the villi than in the apical portion, a nonhomogeneous distribution of blood flow in the intestinal mucosa may be supposed. The presence of two different microvascular plexuses inside the mucosa, corresponding to the cryptal plexus and the villous plexus, supports the above hypothesis. This work studies the intestinal microvasculature in shocked versus normal rats. Forty-five rats were divided into four groups to study the histological damage and the microvascular bed by ink injection, fluorescent microsphere infusion, and resin injection for scanning electron microscopy (SEM) of vascular corrosion cast (VCC) observations. An infusion pressure of 100 ± 5 mm Hg was used in control animals, while 30 ± 5 mm Hg infusion pressure was adopted for controls as well as for shocked animals to simulate physiological or shock conditions. Hemorrhagic shock was induced by removing blood and maintaining a mean arterial pressure of 30 ± 5 mm Hg for 45-120 mins. A close connection among the patterns of microvasculature obtained with VCC and ink injection technique can be appreciated. In normal rats the whole microvasculature was visualized, but in both normal and shocked animals injected at low pressure different patterns could be found, generally showing a highly incomplete visualization of the vascular network. A significant decrease of visualization of both the entire microvasculature and the villous plexus is present in shocked animals when compared to unshocked controls, while no difference in the cryptal plexus visualization was observed. These observations suggest that the cryptal plexus is perfused preferentially during hemorrhagic shock, as a consequence of its peculiar microvascular organization. This may explain the relative resistance of the crypts, compared to villi, to hypoxic injuries in order to sustain endocrine function and the regenerative capability of the mucosa after prolonged hypoperfusion conditions that can lead to villous damage and temporary loss of the intestinal barrier function.
KW - Blood supply
KW - Hemorrhagic shock
KW - Intestine
KW - Microcirculation
KW - Vascular corrosion cast
UR - http://www.scopus.com/inward/record.url?scp=0034069937&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034069937&partnerID=8YFLogxK
U2 - 10.1023/A:1005491509832
DO - 10.1023/A:1005491509832
M3 - Article
C2 - 10759241
AN - SCOPUS:0034069937
SN - 0163-2116
VL - 45
SP - 710
EP - 722
JO - Digestive Diseases and Sciences
JF - Digestive Diseases and Sciences
IS - 4
ER -