A number of changes have been shown to occur in an orderly
sequence after porto -caval anastomosis (Fig. 75).
A strikingchange occurs in body weight. This falls during
the first 20 - 30 days after anastomosis. If the animal survive
a further period of 20 - 30 days of weight stability ensue, and
thereafter there is a tendency for body weight to recover. The
constancy of this pattern of behaviour suggests that the three
phases could be labelled decompensation, balance and recovery.
During the phase of decompensation the liver weight drops to
approximately 40% of the exprted value and remains at the new
proportion to body weight in spite of the phase of recovery.
Plasma ammonium concentration is elevated after shunting, but
the level does not increase with time.
During the phases of decompensation and stability, no changes
in the nervous system have been detected. After 55 days,
morphological changes in astrocytes occur, and the changes appear
to become more prominent with the progression of time (Figs.76 & VT).
These morphological changes are identical with the astrocytic
changes seen in some forms of liver disease and in 'Qiilson's
Throughout the course of the animal 'S ppost operative life
there is an increased rate of DNA synthesis by, and division of
renal tubular cells, without significant accretion of kidney mass.
The rate of turnover of tubular cells probably increases as time
proceeds after anastomosis.
Throughout the course of the animal's post- operativeTLfe,
but particularly in the first 50 days, there is a liability to
haemorrhage from gastric erosions. No chronic gastric mucosal
lesions have been demonstrated.
No evidence for the implication of cerebral monoamine oxidase
in the pathogenesis of hepatic encephalopathy was sustained.
The splenic mass is reduced after porto-caval anastomosis.
The splenic mass is reduced after porto -caval anastomosis.