MICROVASCULATURE OF THE LEFT VENTRICULAR WALL OF THE CANINE HEART STUDIED BY CORROSION CAST METHOD UNDER SEM / 解剖学报

Hearts from eight adult dogs were perfused through both coronary arteries with methylmethacrylate. Small specimens cut out from the left ventricular wall were eroded in 50% HCL for 5-7 days. The replicas were studied under the SEM (S-450). The main results were outlined as follows: The subendocardial capillary plexus composed of varied shapes and orientation of meshes was present. The capillary network of the myocardial layers was consisted of many parallel capillaries and between them a variety of models of anastomoses, such as "H" "K" and "8" modes etc, were observed. In our findings, it was demonstrated that the arteriole and venule were distributed between the myocardial bundles and their direction was often perpendicular to the myocardial bundles. The postcapillary venules were poured into venule by the "ginger or turnip root" arrangement. The replicas of the Thebesian veins were proved in our specimens. The A-V shunting was not observed.

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.

INNERVATION OF THE SINOATRIAL NODE OF THE DOG / 解剖学报

The innervation of sino-atrial node in 5 dogs demonstrated by Faworsky's silver impregnation technique was studied and the results were summarized as follows: 1.On the basis of observation under microscope,two-third of the area adjacent to the suleus terminalis was found to be occupied by the main part of the sino-atrial node in the dog. 2.The nerve ganglia in the sino-atrial node and its peripheral zone were distingu- ished in two groups. 1)The Subepicardial group,i.e,the nerve ganglia of the peripheral zone around the node:It consists of the superficial and profund groups.Most of the nerve ganglia are present close to the sulcus terminalis and become less in number as approaching the cava- auricular angle.The largest nerve ganglion comprising of 30 cells could be seen with naked eye on the section,and the smaller ones are those with individnd cells. 2)Peripheral group around the artery,i,e the nerve ganglia within the node:They were situated around the sino-atrial artereis adjacent to the sulcus terminalis.Occasionally two ganglia may appear in one visual field.They were scattered among the nodal cells and also among myocardial fibers between the sino-atrial node and the endocardium. The characteristics of the structure of the nerve ganglia in both groups were described. 3)The relation of the nerve bundles and the nerve ganglia was studied in detail. The authors presumed that both the parasympathetic postganglionic fibers and parasympa- thetic preganglionic fibers existed in the sino-atrial node.

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%.

THE VASCULAR ARCHITECTURE OF TESTIS IN ADULT MAN / 解剖学报

The vascular architecture of the adult man testis was examined by using thevascular casting method combined with scanning electron microscopy.The circuitousmain branches of testicular artery ran radially from testicular porta towards testicu-lar free border in tunica vasculosa.The test(?)cular surface veins were accompaniedby the main branches of testicular artery and they converged from testicular circum-ference circuitously towards testicular porta.There were centripetal artery andvein as well as centrifugal artery and vein in the septula testis.The intertubularblood vessels and the peritubular capillary plexus were contained in the testicularlobules.The latter was made up of two capillary layers.The outer layer was capil-lary network interwined in fine capillaries.The inner layer was coarse capillarycircles.The interstitial capillary plexus was situated in interstitial tissue between theseminiferous tubules and compose of capillaries arising from the origin of someperitubular capillaries.

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.

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.

BRANCHES AND PATTERNS OF DISTRIBUTION OF THE CORONARY ARTERIES (CORDIS) IN CHINESE / 解剖学报

Observations on the coronary arteries of 100 embalmed hearts from 56 adults and 44 children, have been made. The results are as follows: (1) The point of origin of coronary arteries was found vertically on the margin of the aortic sinus in 69.4% of the left and 52.8% of the right respectively and horizontally at the middle third of the aortic sinus in 79.7% of the left and 67.5% of the right respectively. (2) The external diameter at the opening of the left coronary artery is greater than the right in both adults and children. The mean value of the external diameter at the opening of the left coronary arteries was 0.41?0.14 cm and of the right 0.31?0.02 cm, in children, while in adult, the figures were 0.53?0.02 cm and 0.45?0.02 cm respectively. (3) The accessory coronary artery occurred in 10%.The percentage is lower than other reports in China. (4) The branch and distribution of the left coronary artery were studied thoroughly; its diagonal branch occurred in 38.4%.The mean value of the angle between the left anterior descending branch and the left circumflex artery was about 80?. In one the left circumflex artery was absent. (5) The branch and distribution of the right coronary artery were also investigated carefully. Fifty six percent of the right coronary arteries terminate in the heart, diaphragmatic surface between the crux of the heart and the obtuse margin. The posterior descending branch of right coronary artery ended in the middle-lower third of the posterior longitudinal sulcus of the heart. The occurrence of desending septum artery is 6.1%. (6) An investigation on the posterior superior septum artery and Kugel’s artery has been made: the former, 45.5% of which originated from the right coronary artery, possessed only one branch while the latter, which has been seen in three cases, occurred in 30%. (7) The common type of distribution, in which the posterior wall of the left ventricle was supplied by the right circumflex branch, occurred in 80.2%.

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.

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.