THE ULTRASTRUCTURE OF THE ADULTS' A--V NODES / 解剖学报

Observation had been made on two male adults' hearts.Under electron microscopy,it is found that the A-V node consists of three types of cells,i.e.P cells,transitional cells and Purkinje cells.Because the specimen was cut from the central part of the A-V node, therefore the general myocardial cells were not observed.One of characteristics distingui- shed from the sino-atrial node is the presence of a few Purkinje cells in the A-V node.The number of P cells is far less than S-A node,and the transitional cells are predominant.In the interstitial tissues of the A-V node,the collagenous fibers are not so much as in S-A node but a numbers of capillarie,fibroblasts,mast cells and non-medul- lated nerve fibers can be seen.

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.

MORPHOLOGICAL OBSERVATION ON THE CORONARY ARTERIES OF THE RABBIT HEART / 解剖学报

The coronary arteries of 80 rabbit hearts were studied.Suspension of red lead oxide (Pb_3O_4)in turpentine was injected into the coronary artery.With clearing method and angiographic technique,we studied the branches of the left and right coronary artery, the angle between the anterior descending branch and the left circumflex branch of the left coronary artery,the relationship between the anterior descending artery and the great cardiac vein,the origin of the sinoatrial nodal artery and the atrioventricular nodal artery as well as the type of branch in coronary artery.The results were outlined as follows: 1.The angle between the anterior descending branch and the left circumflex branch is 35～45?in more than one half of the cases(54.5%). 2.The anterior descending branch is often small and short and accompanies the great cardiac vein.It may exist in four forms:1)Both branches run closely to each other. 2)Both run along with each other but leaving a distance in between.3)Both are over- lapping each other.4)Both are crossing each other between the inferior margin of the left auricle and pulmonary artery cone.Ligation of the anterior descending branch in animal experiments should be appropriately made between the right inferior margin of the auricle and the pulmonary artery cone. 3.The left ventricular branch is a direct continuation of the circumflex branch and gives off branches to anterior and posterior wall of the left ventricle. 4.There is an independent ventricular septal artery in the rabbit heart. 5.The sinoatrial nodal artery of the rabbit heart arises frequently from the right coronary artery(86.6%)and the atrioventricular nodal artery from the left coronary artery(72.5%). 6.Commonly the distribution of the coronary blood supply from the left and right coronary arteries to rabbit heart is nearly a balanced circultion(67.5%).Next frequent is the preponderance of the left coronary artery(28.8%),and the preponderance of the right coronary artery occurs only in 3.7%.

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.

SCANNING ELECTRON MICROSCOPIC OBSERVATION ON THE MICROVESSELS IN THE HUMAN SINOATRIAL NODE AND ATRIOVENTRICULAR NODE / 解剖学报

Four fresh corpses of infant are used in this research. Three-dimensional microvasculatures of the sinoatrial node and atrioventricular node were studied by means of the observation of vascular casts with SEM. The results showed that the vascular bed of the sinoatrial node was consisted of the microvascular networks. It was oval in shape. The central artery penetrated this node, through its longitudinal axis and divided progressively into arterioles and precapillary arterioles and finally, they branched into capillary networks at the superficial part of the node. The postcapillary venules were characterized by draining blood in accordance with area. The microvascular construction of atrioventricular node was an oblate microvascular network in shape. There was a layer of delicate capillary networks at its superficial part. In the depth of the capillary networks, the venous plexus which was thick and sinusoidal in shape was observed through the meshes. The artery of atrioventricular node entered the node from one side of it. In the node, the artery ramified by degrees to periphery into precapillary arterioles, which penetrated venous plexus and connected with capillary networks in the superficial part of the node. There were evidently narrow rings, whick were impression of the muscle sphincters at the origin of thep ostcapillary venules.

SCANNING ELECTRON MICROSCOPY ON THE MICROVASCULATURE OF THE MONKEY PAROTID GLAND / 解剖学报

The microvasculature of monkey parotid gland was observed by scanning electron microscope. The capillary networks around the acini were loose and the capillary networks around the ducts were dense and sinusoidal in type. The capillary networks around both the acini and intercalated duct and sinusoidal capillary networks around both the striated duct and intralobular duct were supplied by the blood passing through the acinar or duct arterioles from interlobular and intralobular artery. The capillary networks around the acini showed three draining forms: (1) draining into the vein directly; (2) draining into the capillary network around the striated duct through capillaries; (3) draining into the capillary network around the striated duct through venules. The latter form (venules) is named as "portal system". The capillary networks around the striated duct showed two draining forms: (1) they continued to form the capillary network around the intralobular duct; (2) they converged into venules which accompanied by the intralobular duct. The arterio-venous anastomoses were not observed in the parotid gland. However, arterio-arterial and venovenous anastomoses were found in interlobular region.

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.

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.

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.

THE ULTRASTRUCTURE OF THE ADULTS' A-V BUNDLE, PSEUDOCHORDAE TENDINEAE AND MODERATOR BAND / 解剖学报

The specimens were taken from two adults' hearts, thirty-four and twenty-eight years of age respectively. The A-V bundle was taken from the middle part of postero-inferior edge of the membranous part of the ventricular septum. The moderator band were cut from its superficial and deep part. The pseudochordae tendineae were collected from the left ventricle. All of the samples were fixed by 4％ glutaraldehyde. The chief results were as follows:There are many Purkinje cells in the A-V bundle, moderator band and pseudochordae tendineae. The shape of the Purkinje cells is broader and shorter than the ordinary myocardial cells. The myofibrils and myofiliments of the Purkinje cells are less than of those of the ordinary myocardial cells. The mitochondria of the Purkinje cells were often situated around the nucleus. In the A-V bundle, a few transitional cells and general myocardial cells may be observed. Therefore the His bundle may be consisted of Purkinje cells transitional cells and a few general myocardial cells. Our findings are not in accordance with that of Glomset et al. They observed that the A-V bundle only consisted of the general ventricle myocardial cells. The intercalated discs present between the Purkinje ceils in the A-V bundle were not typical. Besides the intercalated discs, we observed two sorts of the junction types in the A-V bundle: (1) An intercalated disc was observed between a branch of a transitional cell and the lateral surface of the other adjacent transitional cell. (2) Through the collagenous septum, there was a junction between a transverse branch of transitional cell and opposite transitional cell.

OBAERVATIONS ON THE A-S NODE ARTERY AND A-V NODE ARTERY IN CHINESE / 解剖学报

A Study of one hundred hearts (adults 56, children 44) has been made. The S-A mode arteries and A-V node arteries are measured and analysed. The chief results are as fo11ows: (1) 67% of S-A node arteries originated from the right coronary artery; 33% arose from the left coronary artery. A number of the S-A node arteries arising from the right coronary artery were the continuation from the anterior right atrial branch. Occasionally, they may be come from the intermediate right atrial branch or intermediate left atrial branch. (2) The distance between the right S-A node artery origin and the aortic root was about 1.28?0.12 cm in adults, and 0.85?0.09 cm in children, while between the left S-A node artery origin and the bifurcation of the left coronary artery, it was about 0.84?0.19 cm in adults and 0.41?0.03 cm in children. The external diameters of the S-A node arteries were measured. The mean value was as follows: 0.17?0.01 cm (adults); 0.12?0.01 cm (children). (3) The relation between the origins of S-A node artery and A-V node artery may be divided into six types. ①The S-A node artery and A-V node artery which originated from the right coronary artery were about 58.06%. ②The S-A node artery arising from the left coronary artery and the A-V node artery originating from the right coronary artery occurred in 30.11% ③The S-A node artery originated from the right coronary attery, while the A-V node artery arose from the left. This condition was about 6.45%.④The type that the S-A node artery arose from both coronary arteries, and the A-V node artery originated from the right was about 3.22%.⑤Both the S-A node artery and A-V node artery arising from left coronary artery occurred in 1.08%.⑥The A-V node artery originating from the left and right coronary arteries, and the S-A node artery arising from the right coronary artery were about 1.08%.

THE EXPERIMENTAL INVESTIGATION ON THE COURSE OF ESTABLISHING CORONARY COLLATERAL CIRCULATION OF THE HEART IN RABBIT / 解剖学报

The course of estahlishing coronary collateral circulation has been studied after ligating the anterior descending branch of the left coronary artery (L. A. D.) of the heart in 20 rabbits. Another 5 rabbits were studied as control group. The experimental results were as follows: (1) The rabbit electrocardiograms EGG were made before and after the ligation of the L. A. D. The EGG of control group was made only before killing. In these experiments, the pathological changes of No. 28 were observed immediately after ligating the L. A.D. It was found that the T wave was inverted in standard lead I, and that the volts of the QRS complex in lead Vc fell apparently. This phenomenon may be interpreted as myocardial ischemia in the anterior wall of the heart. After ligating the L. A. D. the S-T segment of No. 27 in AVL lead elevated and exceeded I mm, and the depressive Q wave in Vc lead was greater than the one-fourth of the R wave before killing. All of the phenomenen observed in the rabbit entirely confirmed the myocardial infarction and myocardial ischemia. In No. 25, the T wave was inverted in standard lead I, and the QRS complex in lead Vc was not only shallow in depth but also very little. The conditions accounted probably for myocardial ishcmia. During 4 to 21 days after ligating the L. A. D.,the pathological changes in the EGG occurred frequently.The rabbit ECG gradually became normal from 21 st day on. (2) The coronary arteries of the rabbit hearts were injected with X-ray contrast medium and were examined. The X-ray film thus obtained were compared with the specimen after they were cleared. At the same time, sections of the heart walls (the infarcted area and its surrounding areas) of fifteen rabbits were studied carefully under microscope. Our primary impression was that only a few newly formed vessels in the central part of the infarct till the fourth day after ligating the L. A. D. The vessels surrounding of the infarct show a slight winding and distension. During 10 to 28 days, the number of the newly formed vessels in the infarct increased gradually day by day. The vessels surroundings the infarct were also highly crooked and distended, especially in the anterior wall of the right ventricle. This is possibly the most active period in the establishment of coronary collateral circulation. During 28 to 49 days, the morphology of the vessels in the infarct area became similar to that of the corresponding area of the control group. (3) The significance of the coronary collateral circulation on the heart wall was discussed.