Hinton D A, Nelson S R, Gattone V H
Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City.
J Submicrosc Cytol Pathol. 1990 Jul;22(3):345-51.
The paraphysis cerebri is a glandular structure found in the third ventricle of lower vertebrates. It is well-developed in amphibians and reptiles. The function of the gland is not substantiated, but may play a role in calcium metabolism. To further elucidate its possible endocrine role, the paraphyseal vasculature was examined using casting techniques as well as transmission electron microscopy. Perfusion-fixed paraphyses of Rana pipiens and Rana catesbeiana were either: a) cast with Microfil (with subsequent dehydration, clearing, and macroscopic examination) or Batson's compound (followed by tissue digestion and examination by scanning electron microscopy); or b) processed for transmission electron microscopy. The paraphyseal capillary bed consists of a sinusoidal portal system which receives afferent blood from its associated choroid plexus. The choroid plexus of the third ventricle receives its blood supply via arterioles from the posterior telencephalic artery. These arterioles traverse in the periphery of the paraphysis to branch and supply the choroid plexus. Numerous venules exit from the choroid plexus and drain into sinusoids of the paraphysis. The sinusoid venules appear to empty into a midline venous structure which passes tangentially through the paraphysis. The sinusoids consist of fenestrated endothelium which is indicative of transport vessels. Nerve fibers were observed in the paraphysis, however, histofluorescence revealed no monoaminergic sympathetic innervation of the paraphyseal vasculature.
脑旁体是一种在低等脊椎动物第三脑室中发现的腺状结构。它在两栖动物和爬行动物中发育良好。该腺体的功能尚未得到证实，但可能在钙代谢中发挥作用。为了进一步阐明其可能的内分泌作用，采用铸型技术和透射电子显微镜对脑旁体脉管系统进行了检查。对豹蛙和牛蛙的灌注固定脑旁体进行如下处理：a）用微管铸型剂铸型（随后进行脱水、透明和宏观检查）或用巴特森氏复合物铸型（随后进行组织消化并通过扫描电子显微镜检查）；或b）进行透射电子显微镜处理。脑旁体毛细血管床由一个窦状门脉系统组成，该系统从其相关的脉络丛接收传入血液。第三脑室的脉络丛通过来自后脑动脉的小动脉获得血液供应。这些小动脉在脑旁体周边穿行，分支并供应脉络丛。许多小静脉从脉络丛穿出，汇入脑旁体的血窦。血窦状小静脉似乎汇入一个中线静脉结构，该结构切向穿过脑旁体。血窦由有窗孔的内皮组成，这表明其为运输血管。在脑旁体中观察到了神经纤维，然而，组织荧光显示脑旁体脉管系统没有单胺能交感神经支配。
