OBSERVATION ON ANTERIOR MEDULLARY VELUM OF THE RABBIT WITH GROSS DISSECTION AND SCANNING ELECTRON MICROSCOPY / 解剖学报

The present study intended to provide some informations about the relationship between the supraependymal structures (SES) and the periventrieular neural tissue (PVNT), and with gross dissection and scanning electron microscopy the anterior medullary velum (AMV) was observed on 20 adult rabbits. The AMV may be divided into three portions: 1. the posterior membraneous wall of the recess of the inferior colliculus; 2. the anterior roof of the fourth ventricle; and 3. the transiional portion between the two portions mentioned above. On the ependymal surface of the entire AMV. There were numerous microvilli and cilia, except for the second portion of AMV, there were also some spherical-like structures, which were 2-6?m in diameter and had lace-like processes on its surface, and supraependymal cells(SEC) which were stellate, triangular, and spindle in shape. On the cellular surface with very few SEC, the secretory granules may be seen, which were 0.1-0.3?m in diameter. The SEC often extended out 2-5 processes, and the distal parts of which expanded into a flattened shovel-like structure, which lay on or inserted into the ependymal surface. The SEC here are similar to type Ⅱ SEC seen in the third and fourth ventricles, but they may differ significantly in structures on cellular surface, e.g. the secretory granules, and in shapes of their processes. Thus, it may suggest that the SEC here may play an intermediary role between PVNT and CSF, and be another route of neurohumoral modulation.

OBSERVATIONS OF THE PULMONARY CAPILLARY AND ALVEOLAR CASTS UNDER THE SCANNING ELECTRON MICROSCOPE / 解剖学报

Three fresh lungs removed from three male adult dogs were injected with ABS. This material was injected into each lobe of the lung through the pulmonary artery and bronchus simultaneously. The pressure was maintained between 200～280 mmHg. The injected specimens were digested in 20～50％ HCl and peptic solutions for 7～10 days. A part of the cast replicas of the lungs was taken off and gilded with EIKO IB-3. Under SEM (HITACHIS～450) the specimens thus prepared were observed. The chief findings were as follows:Scanning electron micrographs of the injected vascular system presented a clear, three-dimensional picture of extensive capillary networks around the individual alveoli. In the septa between alveoli the capillary networks appeared to be a single layer. These networks looked like pentagonal or hexagonal rings; the meshes in between them were smaller than the vessels themselves.The capillaries observed here in the scanning stereopicture belonged to the category of the alvioli cappilary of the subpleura; the meshes of which were larger than those of other parts.Because the numerous alveoli and capillary networks surrounding the alveoli were filled with the ABS, the position and the shape of the capillary networks can be seen very clearly.The lumen of the alveoli were polyhedron in shape, various in sizes and smooth in contour. Many imprints of the alveolar type Ⅱ cell nuclei existed on the surface. The bridge formation between alveoli were really interalveolar pores; their number and diameter varied. The function of the interalveolar pores was briefly considered in this paper.

STUDIES OF THE HUMAN FETAL LIVER A LIGHT, ELECTRON MICROSCOPIC AND FREEZE-FRACTURE REPLICA STUDY / 解剖学报

The livers from 5 week 14～32 human fetuses were studied. The results are summarized as follows:1. Two kinds of liver cells revealed by EM: the "light" and "dark" cells. The light ones are larger in size, more numerous in number, containing larger mitochondria and obvious RER and SER, but less free ribosomes than the dark ones. Both of them may contain hemosiderin granules and the configuration of mitochondria enclosed by circular or semicircular RER cisternae.2. Bile canaliculus: Beside canaliculi between two adjacent liver cells, canaliculi situated between 3 or 4 liver cells are not infrequently revealed. That is due to the fetal liver cells are arranged in groups rather than in cords. The stereoscopic configurations of bile canaliculus and the tight junction surrounding it are demonstrated more clearly in freeze-fracture micrograph than that of the TEM. In addition, one intracellular bile canaliculus is found in the freeze-fracture preperation.3. The blood sinusoid and hemopoietic focus: In the 4-week fetus, the endothelium of the sinusoid can hardly be recognized While its lumen is quite large. Many erythrocytes accompanied by their immature components can be seen among it. As to the 32-week fetal liver, the endothelium and Kupffer cell may be easily recognized but the lumen of the sinusoid dimenishes enormously. The hemopoietic foci are localized extra-sinusoidially and in close contact with liver cells. Their volume exceeds one half of the fetal liver lobule before the age of 28 weeks, then it dimenishes gradually. In the space of Disse a fat storage cell is revealed.4. The portal canal : The mensenchyma and immature erythrocytes in the portal canal dimenishes with the increase of the fetal age. The portal canal is surrounded by the pigmented limiting plate cells of the liver lobules. The interlobular bile duct is differentiated from the limiting plate cells. Its epithelium is composed of both light and dark cells. The former is more numerous and contains many large mitochondria in its apical portion, while the latter shows higher electron density. Microvilli are located on the surfaces of both kinds of cells and finger like processes in the enlarged intercellular spaces are revealed.

STUDIES OF THE HUMAN FETAL KIDNEY——Ⅱ. FREEZE-FRACTURE ELECTRON MICROSCOPIC OBSERVATION / 解剖学报

A 14-week human fetal kidney was studied by the method of freeze-fracture, the results were as follows:1. All the nuclei of various cells at this stage of development possess distinct nuclear pores with the same diameter and they are distributed randomly on the nuclear membrane. The intramembraneous particles on the PF of both the inner and outer nuclear membranes are more numerous than that of the EF. The morphological features of the nuclear pores vary according to the plane of their fracture face; they appear as dimples on the EF and as valcano mouth on the PF. The interior of the nucleus usually contains homogeneously dispersed particles, but no such structures were seen in thin sections. In some nuclei a round vesicle was revealed.2. The cell membrane of various cells, at this stage, shows special structures to manifest their degree of differentiation. In the less differentiated epithelial cells of the renal tubules, the cell membrane is straight and the intramembraneous particles are randomly distributed, the intromembraneous particles on PF are more than on EF, comparetively well developed tight junctions are located at the latexal surface near the apical portion of the cell while in the differentiated proximal tubules, there are many microvilli on their luminal surface, but their lateral cell membrane is still straight without interdigitations. In some tubules small processes near the basal part may be seen, however, basal fold is still absent. The basal membrane of the renal tubules is very prominent. As to the epithelial cells of the viseral layer of the renal corpuscle, gap and tight junctions are revealed while they are columnar in shape, but as they differentiated into podocyte with primary and secondary processes, the structure of tight junctions become simple, less prominent and discontinuous.3. Cytoplasm: In the process of cell differentiation the amount of cytoplasm increases and the ratio of nuclear end cytoplasmic volume decreases. The orgauelles are less in the undifferentiated cells, so the structure of the cytoplasm of them is much simpler than that of the more differentiated ones. The compartmentation phenomenon of the cytoplasm of differentiated cells become distince. In the freeze-fracture micrographs the membraneous structures, such as mitochondria, Golgi complex and secretion granules etc. are more stereoscopic than those in thin sections, but the opportunity to reveal the fine structures of various cells is minimized due to only one fracture face for each specimen and what structure will be fractured is beyond the control of the operator.

THE EFFECT OF GOSSYPOL ACETATE ON ULTRASTRUCTURE OF HUMAN SPERMATOZOA STUDIED BY FREEZE-REPLICA / 解剖学报

In order to elucidate the ultrastructural changes of human spermatozoa afteradministration of gossypol acetate 40 mg/day for 50 days,freeze-replica techniqueswere employed.In addition to the ordinary changes of spermatozoa,such as swelling,wasting,atrophy,tortuosity,nodulation in the head and/or tail region and fracture betweenhead and tail,the internal structure,biomembrane and intramembranous particles ofsperm also showed relatively more sensitive changes.The changes of biomembranerevealed certain shift in regard to the firmness of reciprocating attachment of inner-and outer-leaflets of the unit membrane.On the other hand,the changes of intra-membranous particles revealed a specialized arrangement,this is,on the plasmamembrane of head and tail they were concentrated into lattice work,whereas,in thehind-head region they accumulated as clusters.In the hind-acrosomal membranetwo types of particles,large and small,may be distinguished,the smaller ones werearranged orderly in lines of all directions.As for the nuclear pores,no changewas found in this study.It is considered that the influences of gossypol upon human spermatozoa,firstof all,were shown in the biomembrane and intramembranous particles,and theordinary changes in appearance were the secondary result.In the discussion,it'ssuggested that a special agent,gossypol receptor,responsible for the gossypol effectsto the sperm,may be present in the plasma membrane of the spermatozoa.

OBSERVATIONS ON THE VASCULAR ARCHITECTURE OF THE GALL-BLADDER IN THE FULL TERM FETUS UNDER THE SCANNING ELECTRON MICROSCOPE / 解剖学报

The SEM specimens of the blood vessels of the gall-bladder in the full term fetus were produced with the methyl methacrylate cast. The specimens were dryed and gilded with EIKO. IB-3. and then observed under scanning electron microscope. The microvessels of the wall of gall-bladder obviously were divided into three layers, namely: serous vessels, muscular vessels and mucous vessels. The serous and muscular vessels are similar to that of the intestinal canal. However the mucous vessels were characterized by subepithelial capillary networks and veins of large calibre in the lamina propria. The capillary networks were connected directly with the venous plexus by the capillaries. There are fewer arterioles passing and branching among the venous plexuses. Each arteriole was connected to capillary networks. The short capillary was seen frequently between the arterioles and the venous plexus, serving as communication between them.

OBSERVATIONS OF THE HUMAN PULMONARY CAPILLARIES AND ALVEOLAR CASTS UNDER THE SCANNING ELECTRON MICROSCOPE / 解剖学报

The architecture of the alveolus and its capillaries of human lung injected withsolution of ABS in methyl ethyl ketone was studied under the SEM.The results wereoutlined as follows:1.The alveolar casts were observed from the subpleural and intralobular septu-lar surfaces.The human alveolus is irregular polygon in appearance.The size ofthe alveolus is variable,its surface is smooth,there are many depressions of the topof type Ⅱ cells.The bridge-like structure between two adjacent alveoli are thecasts of the alveolar pores.They are variable both in size and number,and ofround or oval shapes with smooth surface.2.Capillaries of the subpleural space and interlobular septulum are transitional,and identical in appearance.Meshes of the capillary network are larger than thoseof other parts,but more closer in density compared with those in dog.Each capil-lary is branched from the metaarteriole.3.Capillaries in the alveolar septum is a single layer of dense network,theirdiameter are larger than those of the mesh hole.They originate mainly from thecapillaries of subpleural space and interlobular septulum.

THREE-DIMENSIONAL MICROANGIOARCHITECTURE OF THE SUBMANDIBULAR GLAND IN MONKEY / 解剖学报

In monkey submandibular gland there were two types of capillary networks, which were apparently different in calibre and architecture, i. e. the capillary networks around the acini and the capillary networks around the striated ducts. They originate from their respective precapillary arterioles stemed from intralobular terminal arterioles. Between the two types of capillary networks they are connected by both capillaries and postcapillary venules. The latter were called portal vessels. The capillary networks around the striated duct have two types of draining vessels. First, they converged to form postcapillary venules, which continued to form intralobular veins. Second, they directly continued to form the capillary networks around the intralobular ducts. The capillary networks around the intralobular ducts directly supplied blood through precapillary arteioles around the duct besides they connected respectively with the capillary networks around the acini and striated ducts through capillaries. Furthermore, a ring-shaped constriction was observed distinctly at the intralobular terminal arteriole.

OBSERVATION OF THE VASCULAR ARCHITECTURE OF THE RAT TESTIS / 解剖学报

The gross vessels and microvasculature of the rat testis were observed by clear method and corrosion cast method under SEM. The present study noted that there were two kinds of the microvascular arrangement around the circumference of the seminiferous tubule. The first one could be called the intertubular vessels. This vessel was either individual precapillary arteriole or two parallel capillaries connected by a few small branches to form network. The intertubular vessels were located in triangular columns of interstitial tissue between the seminiferous tubules and parallel with the tubules. The second one could be called the peritubular capillaries. These capillaries connected the intertubular vessels in the manner of a rope ladder, and encircled the seminiferous tubule, formed the peritubular capillary network in the subepithelium of the seminiferous tubule. Authors presume that this vascular feature of the architecture surrounding the seminiferous tubules may be related to high blood flow required in the metabolic activity of the tubules and it may contribute to immediate effect of androgen secreting in the interstitial tissue of the testis on the seminiferous tubules. In the article, the gross vascular feature of the arrangement in the rat testis and the microvascular arrangement in the visceral layer of tunica vaginalis of it is described in detail. Their functional significance is also discussed.

OBSERVATION OF ADULTS' GLOMERULAR CAST BY SCANNING ELECTRON MICROSCOPY / 解剖学报

Two fresh kidneys removed from two male adult bodies, about 48 hrs. after death, were injected through the renal artery with ABS (a copolymer of allyl cyanide, butadiene and styrolene) at a constant pressure between 250-280 mmHg. Corrosion casts were prepared for the study of glomerular vasculature. Small specimens were cut out from the kidney were digested in 20% HCl and 10% peptic solution. Cast replicas of renal arteries and their branches were removed and examined with the SEM (Hitachi H-500 with Scanning accessories HSE_2). The chief results of observation were as follows: The corrosion-cast models of adults' glomerular vessels observed under the SEM consisted of two kinds: the spherical glomerulus and the chrythsanthemum-like glomerulus. The system of capillary loops of the spherical glomerulus was interconnected by anastomosed vessels. The lobular patterns of the glomerular capillary loops as described in the mouse kidney by Hall were not observed. The chrythsanthemum-like glomerulus consisted of many branches of capillaries, either longer or shorter, and most ended blindly. No more than one efferent or afferent vessel have been observed in our corrosioncast specimen of the adults' glomerular vessels. In general, the afferent and efferent arteriole enters or exits at the hilum of glomerulus. Rarely, the efferent vessel left the glomerulus at the oppositeside of the hilum. By-pass tract between the afferent and efferent vessels was not found in our casts. Constrictions of the afferent arterioles such as those shown in rats by Shonyo and Mann ('44) were not demonstrated in the adults' kidneys. Sometimes, there is a constriction near the point of origin of the afferent arteriole.

OBSERVATION ON VASCULAR CASTS OF UVEA NEWBORNS BY SCANNING ELECTRON MICROSCOPY / 解剖学报

Ten fresh eye balls removed from five newborn cadavers were studied.About2-4 hrs after death,cadavers were injected through both common carotid arteries withABS at a constant pressure between 120～150 mmHg.ABS-injected eyes were enucleatedand were cut into halves through equator or meridian.The specimens were digestedin 40% KOH.The corrosion-cast models of blood vessels in uvea were observed underthe SEM.The chief results of observation were as follows:Within the choroid,the blood vessels lie in stratified layers.The large vesselsare located in the outermost layer,next to this layer are smaller vessels.The innermostlayer consists of a continuous single layer of capillaries.The choriocapillaries end around the optic disc.This finding indicates that thechoriocapillaries are not directly involved in the disc circulation.Each short posterior ciliary artery supplied a segment of the choriocapillaries,with some capillary anastomosis between segments,so that the choriocapillaries werearranged in one plane as a single continuous layer of capillaries forming a network.The network of the choriocapillaries consisted of lobules of choriocapillaries.The precapillary arteriole lie in its center.In each lobule meshed capillaries appearedto radiate from a central focus.The postcapillary venule lay on the periphery of thelobule.The lobules varied in their geometric configuration,forming irregularlytriangular to hexagonal shapes.The average size of a lobules of newborn's chorioca-pillaries was 230/420? to 460/520?.The diameter of the choriocapillary varies between8? and 20?.The blood vessels of the ciliary body and iris divide from large circular arteryof iris and long posterior ciliary arteries.Each ciliary process contained a small arterywhich randomly branched to form a capillary network.It is drained by venule.