Alterations in secretion and fine structure of histamine stimulated stomach mucosa following administration of oestrogens

The observation that benign peptic ulceration is less common in females during the reproductive period and the suggestion that oestrogens have an inhibiting effect upon the activity of carbonic anhydrase led us to investigate volumetric and ionic (H+, K+, NA+, C1-.) changes in gastric secretion and also the fine structural changes in gastric oxyntic cells following administration of oestrogens. Fifteen male dogs after 24 hour fasting were anaesthetised with ketalamine hydrochloride and then subjected to a constant i.v. infusion of histamine phosphate, (approx. 14ug/Kg/hour). Twelve dogs underwent truncal vagotomy and ligation at the distal oesophagus. Gastric secretions were collected at 20 minute intervals via a tube introduced into the most dependant part of the stomach through a duodenotomy. The pylorus was ligated around the tube. Approximately 3 hours later, when three consecutive specimens were similar in volume, 4mgm/Kg Premarin (Eguine conjugated oestrogens) was injected i.v. into ten dogs. Further specimens were collected for three hours. Gastric mucosal biopsies were taken from three histamine stimulated dogs before and after injection of Premarin 4mgm/Kg. and were prepared for electron microscopy. The mean hourly volumes of secretion diminished at one, two and three hours after Premarin (ANOVA F 4.5; d.f. 3:33; p< 0.05) with an inhibition of 65.3 percent of the mean pre-Premarin value observed at the third hour. There was a significant rise in the mean pH one hour after Premarin in P<0.05, however, after this there was no significant variation. There was an apparent rise in the mean sodium concentration in the first two hours with a statistically significant rise at three hours after Premarin p<0.05. No significant changes were observed in the mean Potassium or Chloride concentration. The comparison of fine structure of 40 oxyntic cells, 20 before and 20 after Premarin injection, showed an apparent reduction in numbers of canaliculi, with lengthening of the canalicular microvilli. Except for the absence of demonstrable effects on Potassium and on cytoplasmic micro-vesicles these results are comparable with reported findings after inhibition of carbonic anhydrase by acetazolamide (AU)

Effects of oestrogens on carbonic anhydrase activity in human and canine gastric mucosa. The role of carbonic anhydrase inhibitors in the treatment of peptic ulcer - abstract

Carbonic anhydrase which is present in abundance in the mammalian gastric mucosa is concerned with the production of hydrochloric acid. The aim of the present study was to determine whether oestrogens had any effects on the activity of this enzyme in the gastric mucosa of man and dogs. Biopsies were taken from the body of the stomach of 20 male duodenal ulcer patients, 10 of whom had a pre-operative course of diethylstilboestrol. Ten male dogs were used in the animal experiments. Immediately after a biopsy was taken from the anerior wall of the stomach, midway between the cardiac end and the pylorus, 40 mg of equine conjugated oestrogens were injected intravenously in the dogs. Thirty minutes later a second specimen was collected from a site adjacent to the first one. The homogenate obtained from the mucosal layer of each specimen was used for the estimation of its carbonic anhydrase activity by the colorimetric method of Philpot and Philpot. Reaction times were also noted for various dilutions of pure hyophilized carbonic anhydrase. On the basis of a two-tailed test using a 't' distribution it was found that there is a significant difference in the results before and after injection of equine conjugated oestrogens and between the stilboestrol treated patients and the controls. A mean inhibition of 43.5 percent was achieved in man and 21.2 percent in dogs. One patient who was 14 weeks pregnant had an inhibition of 63.4 percent compared with the controls. Truelove and other workers were convinced that ulcer patients experienced symtomatic relief when put on a course of stilboestrol. Similar results were reported in dogs. On the basis of the present work the oestrogens seem to be carbonic anhydrase inhibitors and hence can account for the regular occurrence of hypochlohydria during pregnancy and the lower incidence of peptic ulcer in women of the child-bearing age. Although acetazalamide has been found to reduce the severity of ulcer symptoms, this beneficial action was overshadowed by a concomitant production of persistent acidosis and tingling and numbness in the fingers. The use of carbonic anhydrase inhibitors for the treatment of peptic ulcer merits further investigations. An ideal drug would be a non-feminizing steroid with good peptic ulcer healing powers (AU)

The G F T-A Gastocamera: preliminary report - abstract

The G T F-A Gastrocamera represents a significant advance in the field of gastroscopy with, for the first time, a fiberscope attached to an intragastric camera. With it one can observe and photograph the surface of the gastric mucous membrane and the dynamic movements of the stomach, especially the antrum and pylorus. In this preliminary report 51 gastroscopies were performed by the author on patients who were previously X-rayed. The patients tolerated the procedure extremely well and there were no complications. In 36, cases (70.6 percent) X-ray and gastroscopy were correctly in agreement. In 1 case (1.9 percent) X-ray was indefinite and gastroscopy correct. In 12 cases (23.5 percent) X-ray was wrong and gastroscopy correct. X-ray was right and gastroscopy wrong on 3 occasions (5.8 percent). The radiological errors included 3 cases of antral narrowing ascribed to neoplasm and at gastroscopy a normally wide antrum was seen each time. This supperts the fact that the so-called "narrowed antrum" of the roentgenologists is an ambiguous sign. It calls definitely for gastroscopy when many unnecessary laparotomies will be avoided. In 4 cases gastric atrophy was discovered at gastroscopy, confirming the unanimous opinion that gastritis is best diagnosed at endoscopy. A moderately large ulcer at the incisura was unable to be visualized radiologically after two barium studies. In 2 other cases there were false positive radiological diagnoses of linitis plastica and a benign antral ulcer. 1 case of gastric purpura seen with the gastrocamera was unable to be diagnosed radiologically (AU)