Kiyoshi Koizumi

A comparative histochemical evaluation of various dehydrogenases in the oral squamous epithelium

SummaryA histochemical observation was made of various dehydrogenase activities in oral squamous epithelia. The localization of dehydrogenases showed a relatively similiarity except for the intensity of the dehydrogenase activity. Succinic dehydrogenase activity was generally confined to the basal cell layer and adjacent cell layers; superficial layers did not show any enzymatic activity. Lactic, and malic dehydrogenase activities were localized in the basal cells to st. granulosum, and the activity of lactic dehydrogenase was the highest. α-Glycerophosphate, glutamic, glucose-6-phosphate and TPN-isocitric dehydrogenase activities were observed in all the epithelial cells with the exception for the hornified layer, and they were found generally low. β-Hydroxybutyric dehydrogenase was low and contained in both of st. germinativum and st. granulosum, the keratohyalin in st. granulosum being occasionally found reactive to this enzymatic activity.In connective tissue cells and collagen bundels, activities of lactic, and malic dehydrogenase were intense, while other dehydrogenases were low or trace amount.In the oral squamous epithelium under normal conditions, the dehydrogenase localization concerning the glucose metabolism and TCA cycle member and other close pathways was not similar. Nor were their activities found likewise. Those findings lead to a conclusion that the epithelial cells of the same layer many show a selective metabolic activity.

Pregnancy after combined treatment with bromocriptine and tamoxifen in two patients with pituitary prolactinomas

Two patients with prolactinomas who could not tolerate a large dose of bromocriptine were treated with combination of bromocriptine and tamoxifen. This combined therapy normalized the PRL level and restored a regular ovulatory cycle, which resulted in pregnancy.

Treatment of prolactinoma based on the results of transsphenoidal operations

Ninety-eight patients (16 male, 82 female) with prolactinomas were treated by transsphenoidal operation. The postoperative course was closely related to the tumor size and the preoperative levels of serum prolactin. In 37 (74%) of 50 patients with microadenomas, the levels of serum prolactin returned to normal postoperatively. There were 48 patients with macroadenomas; 27 of these were expansive and 21 were invasive. In 9 (33%) of the 27 patients with expansive macroadenomas, the postoperative levels of prolactin returned to normal; this was not the case in any of the 21 patients with invasive macroadenomas. Of 81 premenopausal women, 35 (43%) resumed normal menstruation postoperatively. All patients with preoperative deficits in the visual field experienced postoperative improvement. There were no postoperative deaths or serious complications in this series. Our data indicate that microprolactinomas are highly curable by transsphenoidal operation alone. In women who plan to have children, prolactinomas should be removed immediately. On the other hand, in patients with macroprolactinomas who manifest high levels of serum prolactin, initial treatment with bromocriptine should be considered because there is little hope for surgical cure and postoperative bromocriptine treatment might be necessary.

Annulate lamellae in prolactin-secreting pituitary adenomas

SummaryElectron-microscopic examination revealed the presence of annulate lamellae in four of five prolactinomas. All the patients examined were 24–30-year-old women who had suffered from amenorrhea and galactorrhea for 3–5 years. Serum levels of prolactin were 114–4,700 ng/ml. The tumors removed by a transsphenoidal approach were 4–23 mm in diameter and showed the ultrastructural features of sparsely granulated prolactinoma. Analysis in correlation with clinical and laboratory data revealed that the annulate lamellae were found in rapidly growing prolactinomas. This is the fifth report on pituitary adenomas with annulate lamellae.

The effect of lisuride hydrogen maleate on anterior pituitary hormones, oestradiol and cortisol in normal and hyperprolactinaemic women

The effects of single oral doses of 0.1 mg lisuride hydrogen maleate (lisuride), a semisynthetic ergot derivative given at 09.00 h, on the serum levels of prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), growth hormone (GH), thyroid-stimulating hormone (TSH), oestradiol and cortisol were studied in six normally cycling women and six patients with hyperprolactinaemic amenorrhoea. The same subjects received placebo and the results were compared with those of lisuride. Within 1 h after oral administration of lisuride, PRL levels decreased significantly (P less than 0.05) and reached the lowest level at 4 h after ingestion and stayed low until 8 h in both normal women and hyperprolactinaemic patients. LH levels slightly but not significantly decreased after lisuride administration in hyperprolactinaemic patients. Serum cortisol levels increased at 13.00 h, probably due to the effect of meal. No significant differences between the lisuride group and placebo group were observed in GH, TSH, FSH and oestradiol levels. These results suggest that lisuride acts as a long-acting prolactin suppressor and that it has little effects on the secretion of other pituitary hormones. Therefore, this drug could be useful for treatment of hyperprolactinaemic patients.