No abstract

SUMMARY Refeeding starved rats with an elemental diet resulted in a marked increase in crypt cell production rate (CCPR) in the proximal small intestine but not in the distal regions of the gut. Little effect on CCPR was noted when inert bulk (kaolin) was added to the elemental diet. Addition of a poorly fermentable dietary fibre (purified wood cellulose) had little effect on intestinal epithelial cell proliferation except in the distal colon where it significantly increased CCPR. A more readily fermentable fibre (purified wheat bran) caused a large proliferative response in the proximal, mid, and distal colon and in the distal small intestine. A gel forming fibre only significantly stimulated proliferation in the distal colon; the rats in this group, however, did not eat all the food given. There was no significant correlation between CCPR and plasma gastrin concentrations, but plasma enteroglucagon concentrations were significantly correlated with CCPR in almost all the sites studied. Plasma PYY concentrations also showed some correlation with CCPR, especially in the colon. Thus while inert bulk cannot stimulate colonic epithelial cell proliferation fermentable fibre is capable of stimulating proliferation in the colon, and especially in the distal colon: it can also stimulate proliferation in the distal small intestine and it is likely that plasma enteroglucagon may have a role to play in this process.

SUMMARY The effects of B-urogastrone/human epidermal growth factor on intestinal epithelial cell proliferation were studied in rats in which intestinal cell proliferation was reduced to a steady state basal level (by maintaining the rats on total parenteral nutrition). Increasing doses of urogastrone progressively raised the two hour collection of metaphases and intestinal weights. The crypt cell production rate was measured in animals maintained parenterally with or without urogastrone, and in rats fed a standard laboratory ration. Continuous infusion of 15 ,ug per rat per day of recombinant beta urogastrone (a dose which has a minimal effect on gastric acid secretion) significantly increased cell proliferation and intestinal tissue weights throughout the gastrointestinal tract. Intravenous infusion of urogastrone was also effective in restoring cell proliferation when it was infused after the intestine had become hypoproliferative. Urogastrone administered through an intragastric cannula thrice daily had no significant effect on either intestinal weight, crypt cell production rate, or metaphase collection.

SUMMARY Refeeding starved rats with a fibre free 'elemental' diet increased crypt cell production rate (CCPR) in the proximal small intestine but not in the distal regions of the gut. Little effect on CCPR was seen when inert bulk (kaolin) was added to the 'elemental' diet. Addition of a poorly fermentable dietary 'fibre' (purified wood cellulose) had little effect on intestinal epithelial cell proliferation except in the distal colon where it significantly increased CCPR. A more readily fermentable 'fibre' (purified wheat bran) caused a large proliferative response in the proximal, mid and distal colon and in the distal small intestine. A gel forming 'fibre' also stimulated proliferation in the distal colon. There was no significant correlation between CCPR and plasma gastrin concentrations, but plasma enteroglucagon concentrations were significantly correlated with CCPR in almost all the sites studied. Plasma PYY concentrations also showed some correlation with CCPR, especially in the colon. Thus, whilst inert bulk cannot stimulate colonic epithelial cell proliferation, fermentable 'fibre' is capable of stimulating proliferation in the colon, and especially in the distal colon: it can also stimulate proliferation in the distal small intestine and it is likely that plasma enteroglucagon may have a role to play in this process.

The technique of embryo transfer can have a great impact on the outcome of in-vitro fertilization (IVF) treatment. Transcervical embryo transfer is a blind procedure and difficulty can unexpectedly arise. Many IVF programmes therefore perform a 'mock' embryo transfer prior to the treatment cycle to determine the most suitable catheter and technique for transfer. This, however, adds an extra separate procedure with time and cost implications. Moreover, as the uterus is mobile, its direction may vary on the day of the embryo transfer from what it was during the mock embryo transfer. Performing mock embryo transfer immediately before the real transfer would circumvent these problems. We report here on 113 embryo transfer procedures where a 'step-wise' mock embryo transfer protocol was performed with a full bladder immediately before the embryo transfer. The number of embryos transferred (mean +/- SD) was 2.6 +/- 0.67, the pregnancy rate per embryo transfer was 45.1%, and the intrauterine implantation rate per embryo transferred was 20.6%.