Receptor concentrations for estradiol and progesterone in surgically induced endometriosis in the rat.

In order to obtain more detailed information about the validity of the rat as an endometriotic experimental model, endometriosis was surgically induced in 48 female Wistar rats, and the estrogen (ERc) and progesterone (PRc) receptor concentrations present in experimental endometriosis and endometrium were compared in the four estrous phases (n = 12). Lower values of ERc were found in endometriosis than in endometrium (proestrus, 156.27 +/- 24.09 vs. 195.27 +/- 32.13 pmol/g tissue, P < 0.05; estrus, 302.33 +/- 45.16 vs. 335.67 +/- 44.82 pmol/g tissue, P < 0.05; metestrus, 166.60 +/- 26.09 vs. 193.30 +/- 22.04 pmol/g tissue, P < 0.05; diestrus, 130.27 +/- 20.58 vs. 135.81 +/- 16.25 pmol/g tissue, P > 0.05; Student's t-test). As in the case of ERc, lower PRc were observed in endometriotic than in endometrial tissues (proestrus, (proestrus, 137.83 +/- 22.64 vs. 176.54 +/- 21.78 pmol/g tissue, P < 0.05; estrus, 242.10 +/- 34.78 vs. 286.20 +/- 31.74 pmol/g tissue, P < 0.05; metestrus, 194.36 +/- 35.08 vs. 224.73 +/- 20.21 pmol/g tissue, P < 0.05; diestrus, 147.72 +/- 26.21 vs. 147.33 +/- 22.65 pmol/g tissue, P > 0.05; Student's t-test). Similar ERc/PRc ratios were found for both the endometriotic and the endometrial tissues (proestrus, 1.14 +/- 0.07 vs. 1.08 +/- 0.09, P > 0.05; estrus, 1.29 +/- 0.19 vs. 1.21 +/- 0.18, P > 0.05; metestrus, 0.87 +/- 0.14 vs. 0.89 +/- 0.11 P > 0.05; diestrus, diestrus, 0.89 +/- 0.06 vs. 0.92 +/- 0.06, P > 0.05; Student's t-test, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

Uterine horn replacement in the rat using denervated and devascularized jejunum.

In the hope of identifying suitable material for reconstructive tubal and uterine surgery, the authors have replaced a portion of the uterine horns of two groups of Wistar rats (n = 10) with normal (VAS group) or with denervated and devascularized jejunal grafts (NVAS group). All grafted horns stayed patent. No pregnancy was observed in the uterine horns operated on. The light microscopic appearance of the grafts was studied and compared by ANOVA. Three months after surgery in the VAS group, the number (51.4 +/- 9.5) and height (309.8 +/- 44.7 microns, P less than 0.05) of the villus, the Lieberkühn cripts height (156.9 +/- 34.9 microns) and the number of goblet cells per cript (7.2 +/- 1.2, P less than 0.05) had decreased in relation to their corresponding control jejunal fragments (57.7 +/- 5.4; 345.1 +/- 18.0 microns; 192.2 +/- 40.8 micron; 12.4 +/- 1.9, respectively). Three months after surgery, the intestinal structure was maintained in the anastomosis areas of the NVAS group, therefore the mucus production of the jejunal-graft mucosa was not completely eliminated. No villus or crypts were observed, but a monostratified cubic-cell-type epithelium at the NVAS jejunal graft mid-portion, along 58.1 +/- 12.9% of the total length of the intestinal graft. Under this epithelium a connective tissue, like a non-glandular submucosa, was apparent.

Postoperative adhesion after uterine horn surgery in the rat, with the use of TC7.

The influence of TC7 in adhesion prevention was tested on 24, 2.5-month-old Wistar rats. Their right and left uterine horns were homogeneously allotted into four experimental groups, each of 12 horns. The groups were as follows: Group C (n = 12), that underwent cuts along 1 cm in the serosal layer; Group TC (n = 12), where the uterine horn was only surrounded with 3 layers of TC7, 1 x 1 cm in size; Group C+TC (n = 12) in which the serosal cuts were covered with TC7, as in group TC and an untouched control group (n = 12). All uterine horns were kept in uniform contact with the intestinal serosa layer by means of two 8/0 nylon stitches spaced 2 cm apart, so that the adhesion surfaces were the same in all groups. Lengths in mm and severity adhesions (0 = no adhesion to 3 = severe adhesion) were recorded. The injury in group C caused extensive (8.83 +/- 4.77 mm) and dense adhesions (score 2.42 +/- 1.11) in 83.33% of the cases. No significant differences were observed compared with the C+TC group (8.08 +/- 5.45 mm, score 2.25 +/- 1.30; P > 0.05, ANOVA). Significantly, more adhesions were observed on the C and C+TC Groups than in the control (1.00 +/- 2.27 mm, score 0.16 +/- 0.37) and TC (3.08 +/- 3.38 mm, score 1.00 +/- 1.15) groups (P < 0.05, ANOVA). TC7 does not appear to be an effective agent for preventing postoperative adhesions in this animal model.

Influence of prostaglandins E2 and F2 alpha on passage pressure across the uterotubal junction and isthmus in the rat.

The influence of prostaglandins E2 and F2 alpha on passage pressure across the uterotubal junction (UTJ) and isthmus were studied in rats that were either in the pro-oestrus, oestrus, metoestrus or dioestrus phases. Effects of these prostaglandins were also investigated in rats that had been either ovariectomized and treated with oestradiol or medroxiprogesterone acetate, or only ovariectomized. In each rat, the left UTJ was surgically resected and the isthmus anastomosed to the uterine horn, whereas the right UTJ was left untouched. The passage pressures across the left isthmus and the right UTJ were measured before and after prostaglandin treatment. The pressures obtained in the UTJ in the oestrus phase and oestrogen-treated ovariectomized animals were lower than those registered in the remaining groups. Prostaglandin E2 decreased the pressures when compared with pre-treatment measures in all groups. Significantly higher pressures were registered across the UTJ in prostaglandin F2 alpha than in E2 treatment, with these higher pressures being similar to pre-treatment pressures. Both hormonal changes throughout the oestrous cycle and prostaglandin E2 treatment had a similar influence on the passage pressure across the isthmus, as that described for UTJ, but with lower values. The results indicate that prostaglandin E2 decreases the passage pressure across both UTJ and isthmus and can have an influence on the regulation of transport across these 2 areas.

Passage pressure across the uterotubal junction during the 4 phases of the oestrous cycle in the rat.

The closure strength of the uterotubal junction (UTJ) was measured in 90 2.5 month old cycling female Wistar rats, assigned to 9 groups of 10 each. The passage pressure in both left and right UTJ were registered in pro-oestrus, oestrus, metoestrus and dioestrus phases. Five other groups were formed with rats which had been treated for 3 weeks with oestradiol (group E) or medroxiprogesterone acetate (group P), and with animals which had been ovariectomized 75 days prior to registering the pressure (ovariectomized group) or ovariectomized and treated with oestradiol (group Ov-E) or medroxiprogesterone acetate (group Ov-P). The passage pressure of the right and left UTJ in each animal was similar in each of the groups. The pressures obtained in the oestrus phase or in the E and Ov-E groups were significantly smaller than those registered in dioestrus or in the P and Ov-P groups, and only slightly smaller than that obtained in the pro-oestrus and metoestrus phases. The results indicate that the swelling of the mucosa mediated by oestrogens is not the cause of the tubal locking in the rat.

Microfilariae in the mammary gland of a bitch.

A microfilarial infection of the mammary gland of a bitch with Dirofilaria immitis was diagnosed by fine needle aspiration biopsy. The animal had had a progressively enlarging, painful, pendulous, cystic swelling, measuring 12 x 18 cm, in the second left abdominal mammary gland for four to five months. Two separate biopsies revealed microfilariae and mammary duct epithelial cells, but no inflammatory cells. A histological examination revealed atrophic and necrotic mammary lobules with dilated and cystic ducts. Solid carcinoma was also observed in a small area of the mammary mass. The interlobular connective tissue was oedematous and the lymphatic and vascular channels were dilated. Microfilariae were observed within both the small blood vessels and capillaries and in the interlobular stroma of the mammary tissue, but there was no evidence of an inflammatory response.

Effects of TC7 associated to 32% dextran 70, heparin and carboxymethylcellulose in adhesion prevention in the rat.

Experimental studies on adhesion formation 90 days after laparotomy in the rat were done. Uterine horn adhesions after standardised procedures and trauma in a control group of 10 rats were compared with those obtained in six other 10-rat groups in whom heparin, carboxymethylcellulose (CMC), 32% dextran 70 and the fabric TC7 either alone or in various combinations were used at the time of laparotomy. Dextran 70 and CMC used on their own appeared to reduce adhesion formation but the improvement did not achieve statistical significance when compared with the control group. TC7 used alone had no anti-adhesion effect; when used with CMC or dextran 70, TC7 did not enhance the anti-adhesion benefit conferred by either substance used on its own.

Anastomosis of uterine serosa with cyanoacrylate versus suture in rats.

Experimental end-to-end uterine horn anastomosis was performed in 20 Wistar rats with the conventional technique of microsurgery, with n-butyl-cyanoacrylate and with cyanoacrylate with the addition of one or two microsutures. Only in the case of conventional anastomosis and of cyanoacrylate in combination with two microsutures, was the patency rate 100%, whereas in the case of uterine horns anastomosed with cyanoacrylate alone, the patency rate was 80%. Histologic findings revealed the presence of tissue adhesive encysted in the serosa with a moderate inflammatory reaction around it, remaining two months after surgery. On the 60th day, the muscularis layer was only continuous in the conventional and cyanoacrylate with two microsutures groups. Our findings indicate that tissue adhesive and two sutures used together may offer a viable alternative to sutures for genital duct anastomosis.

Study of two simplified microsurgical techniques for uterine horn anastomosis in rat.

This study compares two simplified techniques, which use only 2 and 4 sutures respectively, with a conventional technique with 8 sutures for fallopian tube anastomosis. Experimentally these techniques were performed on the uterine horns of fifteen female rats. A 100% patency rate was obtained with all three techniques. No difference in the mucosal, muscular and serosal regeneration was observed in the three groups at 10, 20 and 60 days. Two months after surgery, the serosa, muscularis and mucosal layers were completely continuous in all groups. The operating with 2 sutures (5'30" +/- 1'10") was significantly less than with 4 (9'09" +/- 0'55", P < 0.05 ANOVA) and 8 sutures (15'12" +/- 1'41", P < 0.05 ANOVA). A minimum inflammatory reaction to sutures was observed in all three groups at 60 days after surgery. The results suggest that with 2 sutures are all that is needed for tissue repair.

Structural changes of a devascularizated colonic graft when its replaces the rat uterine horn.

A one centimeter length of the left uterine horn in two groups of Wistar rats (n = 10) was replaced with normal (VAS group) or with denervated and devascularizated (NVAS group) colonic grafts. All animals maintained pregnancy in the right control horns but not in the grafted horns. At 40, 60 and 90 days after surgery, the light microscopic appearance of the autografts was studied. In the VAS group, and with respect to the last period, the number (5.5 +/- 0.7) and height (1.0 +/- 0.1 mm, P < 0.05 ANOVA) of the folds, the intestinal glands height (160.2 +/- 21.2 mu, P < 0.05 ANOVA) and the number of globet cells per gland (26.6 +/- 4.2, P < 0.05 ANOVA) had decreased in relation to the colon control (6.0 +/- 0.7, 1.4 +/- 0.1, 251.7 +/- 31.8, 42.6 +/- 5.2 respectively). A similar intestinal structure to that described above was observed in the anastomosis areas of the NVAS group, and therefore a decreased mucus production was maintained in this areas. No folds or intestinal glands were observed, but a monoestratified cubic epithelial cells type was observed along 63.7 +/- 4.1% of the NVAS colonic graft center. Under this epithelium a connective tissue, like a non-glandular submucosa, was obtained.