Immunohistochemical analyses of parathyroid hormone-dependent downregulation of renal type II Na-Pi cotransporters by cryobiopsy

The “in vivo cryotechnique” (IVCT) is a new method of morphological analysis which has the advantage of freezing tissues in living animals without stopping their blood circulation. The purpose of this study was to investigate the effect of parathyroid hormone (PTH) on renal type II Na-Pi transporters (NaPi-IIa and NaPi-IIc) and ”cryobiopsy” (CB) using special cryoforceps as a simple method of the IVCT. The kidney tissues were biopsied at various time points after PTH administration by CB using liquid nitrogen as the cryogen. By hematoxylin-eosin (HE) staining the kidney tissues, well-frozen areas without visible ice crystals were obtained in the tissue surface areas, and the brush border membrane (BBM) of proximal tubules was well preserved at a light microscopic level. Immunohistochemical evaluation showed that PTH downregulated NaPi-IIa and NaPi-IIc at the BBM, being controlled by a different mechanism. In this method, the PTHinduced internalization of NaPi-IIc from microvilli to subapical compartments was not observed in the tissue preparations. NaPi-IIc protein appears to be degraded in microvilli of the proximal tubular cells after the injection of PTH. We suggest that CB using liquid nitrogen is useful to investigate renal type II Na-Pi transporters at the light microscopic level

A preliminary list of the vascular plants of Higashi-hiroshima Campus, Hiroshima University, Hiroshima Pref., SW Japan <Data>

広島大学東広島キャンパスは広島県西条盆地の中央部に位置し，その敷地内には様々な植物が生育している。キャンパス内の維管束植物に関しては学内誌などに断片的に紹介されてきたが，1995年の移転完了後，網羅的な植物相の調査は行われていない。本稿ではキャンパス内の植物相の現状を把握するため，文献および生態実験園とぶどう池周辺を中心に行った調査にもとづいて，東広島キャンパスの維管束植物目録（101科210属286種）をまとめた。A preliminary list of the vascular plants of Higashi-hiroshima Campus in Hiroshima University (Hiroshima Pref., SW Japan) was reported based on own field researches and previous reports. A total of 286 native, naturalized and garden species, including infraspecific taxa, were recorded