Baseline performance of the ischaemic button model for induction of adhesions in laboratory rats

Abstract

The ischaemic button model is frequently used for the induction of adhesions in laboratory rats. Male rats are often used because of the common belief that the peritesticular (intra-abdominal) fat in males facilitates adhesion formation, although this theory is not evidence based. Comparing the model's performance in both sexes is an important aspect of refining animal experiments. The aim of this study is to compare baseline performance of the modified ischaemic button model in both male and female rats. Follow-up was 1 week and noted endpoints were intra-abdominal adhesion formation and differences in welfare assessment. A total of 192 ischaemic buttons (96 male/96 female) were created in 24 Wistar Han rats (12 male/12 female). After 1 week of follow-up, 93 buttons survived in the male group (96.9%) compared with 91 in the female group (94.8%) (p = 0.409). In the male group, 85 out of 93 (91.4%) buttons induced adhesions compared with 84 out of 91 (92.3%) in the female group (p = 0.881). All but one animal had a Zühlke score of 3. There were no clinically relevant differences in welfare scores. Male animals increased in weight significantly faster compared to females (p < 0.001), after correcting for physiological growth. The ischaemic button model resulted in equal quality and quantity of intra-abdominal adhesions in both male and female Wistar Han rats. Both male and female Wistar Han rats are suitable for the induction of experimental adhesions in the ischaemic button model.

Prevention of incisional hernia using different suture materials for closing the abdominal wall: a comparison of PDS, Vicryl and Prolene in a rat model

“…The animals were socially housed in filter-topped cages with a 12 h daynight cycle and had free access to food and water. Because of hormonal influences on wound healing by progesterone and oestrogen [27] and a faster postoperative weight recovery of males compared to females [28], only male rats were used in this experiment. The animals were randomly assigned to one of the three groups for abdominal wall closure of two separate midline incisions by either Prolene 4/0, PDS 4/0 or Vicryl 4/0.…”

Comparing Five New Polymer Barriers for the Prevention of Intra-abdominal Adhesions in a Rat Model

“…The same has been described in a previous report. 14 The Nair score lacks finesse in this model in contrast to for instance the cecal abrasion model, where a more confined area is scored for adhesions. Scoring the four quadrants of the abdomen separately would increase the precision but would also allow room for error because of the small size of the abdomen of the rat.…”

“…On each side of the midline incision, four ischemic buttons were created, 1 cm lateral of the incision and 1 cm apart. [11][12][13][14] After creating the buttons, a previously designated experimental barrier, HA-CMC barrier or no barrier was placed according to the randomization. Two barriers (A3 and B2) had one roughened side that was placed facing the abdominal wall.…”