Influence of the menstrual cycle on aminolevulinic acid induced protoporphyrin IX fluorescence in the endometrium: in vivo study

BACKGROUND AND OBJECTIVES: In vitro studies indicated that compared to postmenopausal women, premenopausal women had increased aminolevulinic acid induced protoporphyrin IX (ALA-induced PpIX) fluorescence expression in the endometrium. The aim of this study was to evaluate menstrual cycle dependency of ALA-induced PpIX fluorescence in the endometrium in vivo. STUDY DESIGN/PATIENTS AND METHODS: Thirteen patients were included for in vivo spectrofluorometric measurements of ALA-induced PpIX in the endometrium and 51 patients for fluorescence hysteroscopy. Two milliliter of a 2% 5-ALA-solution at pH = 4.0 (ASAT AG/Zug, Switzerland) was topically administrated just before spectrofluorometry and 4 hours before hysteroscopy. Spectrofluorometry: Optical fiber based. Fluorescence hysteroscopy: STORZ-D-Light system (Storz, Tuttlingen, Germany). Histological classification of curettage and bioptic endometrial tissue stained with hematoxylin and eosin (H&E). RESULTS: Hysteroscopic and in vivo spectrofluorometric measurements showed an increase of ALA-induced PpIX fluorescence in the secretory and hyperplastic endometrium compared to proliferative and atrophic endometrium. CONCLUSIONS: The accuracy of fluorescence hysteroscopy and the success of the photodynamic endometrial ablation using ALA-induced PpIX may depend on the hormonal influence of the menstrual cycle. The mechanisms responsible for the increased ALA-induced PpIX fluorescence in the secretory versus proliferative phase of the menstrual cycle deserve further studies.     

An autoradiographic study of the organization of intrahippocampal association pathways in the rat

The longer associational connections of the hippocampal formation have been studied autoradiographically in a series of adult rats after small injections of ³H-amino acids into each of its various cytoarchitectonic fields. The major findings can be summarized as follows. The dentate gyrus projects in a topographically ordered manner upon the pyramidal cells of the regio inferior by way of the supra- and infrapyramidal bundles of mossy fibers. Certain cells in the hilar region of the dentate gyrus (which operationally may be defined as constituting field CA₄ of Ammon's horn) give rise to a hippocampodentate projection to the inner one-quarter of the molecular layer of the dentate gyrus. Either the same or closely related cells give rise to fibers which join the Schaffer collateral system from field CA₃ to the stratum radiatum and stratum oriens of the regio superior. The regio inferior is also characterized by a longitudinally directed associational bundle which runs throughout the septo-temporal extent of the hippocampus and is centered in the region of subfield CA_3a. The regio superior has no reciprocal projection to the regio inferior but sends a substantial projection back to the subiculum and to the entorhinal area. There is also a projection to the subiculum from the regio inferior, and the subiculum itself probably contributes significantly to the projection to the entorhinal and perirhinal cortices. There is a striking parallelism between certain of these associational connections and the commissural projections to the hippocampus and dentate gyrus. Each cytoarchitectonic field that contributes a commissural projection also gives rise to an ipsilateral associational pathway which in its intrahippocampal course and its mode of termination exactly matches that of the commissural projection, although in general, the associational connections are more extensive in their distribution along the septo-temporal extent of the hippocampus than the corresponding commissural connections. The reverse is not true; there are a number of associational projections which are not paralleled by commissural projection. All of the associational projections are topographically arranged, but those which extend across the transverse axis of the hippocampus usually show considerable divergence so that afferents from different levels overlap fairly considerably within their respective projection fields.     

Early ultrastructural changes in RU-486-exposed decidua

An antiprogesterone (RU-486) was administered to women undergoing voluntary interruption of pregnancy. Five patients received 100 mg 12 h before surgical interruption, 5 others received 100 mg twice, 24 and 12 h before interruption, respectively, and another 5 received no drug at all and served as controls. Placentas and deciduae were examined morphologically with the light microscope and by electron microscopy. No specific lesions were detected in placental tissue. With conventional histology, the deciduae showed various degrees of interstitial edema and necrosis, changes which did not enable a distinction between treated cases and controls, although stromal disintegration tended to be more marked in RU-486-treated patients. At the ultrastructural level, the endothelium of decidual capillaries showed striking hyperplasia of the endoplasmic reticulum. Morphometric evaluation showed a statistically significant difference between RU-486-treated patients (2 X 100 mg) and controls. A possible link between these morphological changes and the induction of prostaglandin synthesis by the antiprogesterone is suggested. However, the full significance of the observed lesions remains uncertain and does not allow definite conclusions concerning the abortifacient effect of RU-486.