Adenosine triphosphatase activity in the carotid rete-cavernous sinus complex of sheep and goats

The carotid rete-cavernous sinus structures of sheep and goats were frozen with liquid nitrogen or with Freon liquid spray and were cryo-sectioned at -20 C. The main concentration of sodium- and potassium-dependent adenosine triphosphatase was on the tunica intima, especially on the endothelial cells of rete branches and the cavernous sinus. Little reaction product was discernible in the tunica media and the tunica adventitia.     

Gross and histologic study of the rostral epidural rete mirabile and the cavernous sinus in one-humped camels

Gross and histologic features of the rostral epidural rete mirabile (carotid rete) and the cavernous sinus in one-humped camels were studied. It was evident that the branches of the carotid rete share a common tunica adventitia with the veins of the cavernous sinus. Transmission electron microscopy of the rostral epidural rete mirabile and the cavernous sinus revealed gap junctions in endothelial cells lining the walls of the arterial rete branches and veins. The internal elastic lamina of rete branches were fenestrated. Some of these structural features could facilitate countercurrent heat exchange between the rete branches and the venous plexus of the cavernous sinus to regulate brain temperature.     

The Evidence of Carotid Body in the Carotid Rete of the Shiba Goat

The carotid body was found in/on the cavernous sinus of the carotid rete of the Japanese miniature Shiba goat by light and electron microscopies. The carotid body-like aggregated cell group consisted of two types of cells arranged in the lobule. The first type contained membrane-bound granular vesicles; these cells resembled to the type-I cells in the carotid body. The second type contained no cytoplasmic vesicles, and were located in the periphery, investing the type-I cells. These features appear to be consistent with those of the type-II cells in the carotid body. The nerve ending showed two peculiar features in the intercellular space of type-I cells. The clear vesicle-containing nerve ending showed a structural feature indicative of efferent synapsis. The small granular vesicle-containing nerve ending has been described as a baroreceptor-like ending by VERNA (1979). All of these features are typical characteristics of the carotid body.     

双峰驼脑硬膜外异网

本文用动脉内注射红色油画颜料,红色乳胶溶液的大体解剖学方法,解剖了15例双峰驼,研究了双峰驼的脑硬膜外异网,并追踪了进入和传出硬膜外异网的血管。结果发现双峰驼有发达的硬膜外异网,部分位于颅内硬膜下海绵窦内,部分位于眶圆孔和翼腭窝后部。构成异网的血管来自颈内动脉和颌内动脉的分支吻合动脉,这些动脉进入海绵窦后立即分支互相吻合形成异网;在异网的背内侧部这些吻合支又聚集形成颈内动脉颅内段和后交通动脉自海绵窦传出并互相连接形成大脑动脉环。在异网中找不到颈内动脉贯穿异网的迹象,这一点与牛的硬膜外异网不同。     

Countercurrent transfer of 125I-LHRH in the perihypophyseal cavernous sinus-carotid rete vascular complex,demonstrated on isolated pig heads perfused with autologous blood

The objective of the study was to determine whether the local permeability of luteinizing hormone-releasing hormone (LHRH) from the venous blood of the perihypophyseal cavernous sinus into the arterial blood of the carotid rete, supplying the brain and hypophysis in gilts, depends on the day of the estrous cycle, as well as to determine whether this transfer exists when LH concentration in the blood is reduced (the experimental short-loop negative feedback for LH secretion after estradiol injection in ovariectomized gilts). Experiments were conducted on isolated gilt heads with necks, on chosen days of the estrous cycle (n = 40), and on previously ovariectomized gilts treated with estradiol benzoate (EB) (n = 5) or corn oil (n = 3). After exsanguination, the gilt heads with necks were disarticulated and about 30–45 min later were supplied with autologous, oxygenated, and heated blood at a stable blood flow and pressure through the left carotid artery for 30 min. ¹²⁵I-LHRH was infused into both cavernous sinuses through the cannulated angularis oculi veins for 5 min. After ¹²⁵I-LHRH infusion, radiolabeled LHRH was found (P < 0.001) in arterial blood taken from the carotid rete through the open right carotid artery in all animals used in the experiment: on Days 1–2 (six gilts), on Days 12–14 (seven gilts) of the estrous cycle, and in five ovariectomized gilts during negative feedback for LH surge (40 hr after EB). No significant radioactivity of ¹²⁵I-LHRH was found in the arterial blood on Days 3–5 (n = 6), 9–11 (n = 4), and 15–21 (n = 17) of the estrous cycle. A very low level of radioactivity was found in the ovariectomized control group after the injection of corn oil (n = 3). These results provide evidence for the permeability of LHRH from the venous to the arterial blood and its retrograde transport with the arterial blood to the hypophysis and brain, after the ovulation period (Days 1–2) and on Days 12–14 of the estrous cycle. This suggests that a close relationship exists between the day of the estrous cycle and LHRH permeability from the venous to the arterial blood in the perihypophyseal cavernous sinus—the carotid rete complex in gilts—and that this mechanism may be included in a short-loop feedback for LHRH secretion.     

Histological and ultrastructural studies on the coronary artery of adult domestic dog (Canis familiaris)

The objective of this work was to study the histological structure of the dog's coronary artery by light and transmission electron microscope (TEM). The coronary artery consisted of three tunics: tunica intima, tunica media and tunica adventitia. The tunica intima consisted of endothelium rested directly on internal elastic lamina without the subendothelial connective tissue layer. The tunica media were composed of smooth muscle fibres interspersed with few elastic and collagen fibres. The tunica adventitia consisted of collagen and elastic fibres intermingled with fibroblast cells; it had vasa vasorum and nervi vasorum. Some histomorphometric measurements were performed and compared statistically. The ultrastructural study showed that the endothelial cells were communicated through complex junctions and characterised by filiform cytoplasmic processes passed through the opening of the underlying internal elastic membrane. The smooth muscle fibres of tunica media communicated with each other through cytoplasmic processes. The tunica adventitia showed minute non-myelinated nerve. This work revealed that the dog's coronary arteries are typical muscular arteries, which show little structural variations from that of other mammals.     

Histological Assessment of Selected Blood Vessels of the Phocid Seals (Northern Elephant and Harbour Seals)

Phocid seals exhibit vascular adaptations that allow them to undertake prolonged deep dives. These vascular adaptations are either unique to phocids, or are modified vascular equivalents to those present in terrestrial mammals. One such adaptation, the aortic bulb, is a spherical enlargement of the ascending aorta specific to phocid seals. Its histological make‐up consists of a reinforced tunica media with circular and longitudinal layers of elastic fibres. This reinforcement enables multi‐axial deformation of the aortic bulb, thus complementing its function as a prominent elastic reservoir or ‘windkessel’. A second adaptation, the hepatic sinus, is an asymmetrical dilation of the abdominal portion of the caudal vena cava and accompanying hepatic veins. The hepatic sinus is comprised of a relatively thin tunica media, with a scant smooth muscle component. The bulk of the sinus wall is comprised of tunica adventitia. A third vascular adaptation distinctive to the phocids is the pericardial venous plexus, composed of convoluted veins circumnavigating the perimeter of the heart. Microscopically, these veins have a thick tunica media and also contain valves. Smaller arteries, venules and distinct capillary beds are observed interspersed in‐between these veins. It can be hypothesized, that in seals, certain vascular embryonic development may be arrested at an earlier embryonic stage, resulting in these unusual vascular formations. These modifications play a vital role in blood pressure regulation and distribution of oxygenated blood during prolonged deep diving. The purpose of this work was to elucidate the histological aspects of these unique vascular modifications and relate them to specific function.     

Surgical technique to cannulate the rete testis of the goat

A surgical technique was devised to collect rete testis fluid from 14 mature goats. The tubular portion of the extratesticular rete testis was cannulated where it penetrated the tunica albuginea of the testis under the center of the head of the epididymis. The tip of the cannula was sutured in place in the extratesticular rete testis and the opposite end was passed through the scrotum and into a plastic collection bottle. The bottle was glued to pillow ticking, which was sutured to the scrotum. Continuous flow of rete testis fluid occurred for 0 to 14 days and was usually terminated by a sperm clot in the cannula. The flow rate was 0.59 +/- 0.37 ml/hr.     

Dural sinuses in the pig and their extracranial venous connections

The dural sinuses of the pig and their connections with veins of the head and neck have been described. The rostral epidural rete mirabile and the cavernous venous sinus complex have been described in detail, and speculation about their possible role in brain temperature regulation was made.     

Das Rete mirabile der Arteria maxillaris des Löwen (Panthera leo, L. 1758)

Seventeen lion heads were examined. Their arteries were injected with colored supervinyl-chloride (dissolved in acetone) after which the heads were macerated biologically. The rete mirabile of the maxillary artery was located extracranially and was formed by numerous arteries that arose from the dorsal and medial surfaces of the maxillary artery. The rete released branches (rami retis) which entered the cranial cavity through the orbital fissure where they anastomosed with the intracranial segment of the internal carotid artery. The extracranial portion of the internal carotid was found to be obliterated. Some other arteries leaving the rete anastomosed with the internal ophthalmic artery before it entered the optic canal. The following further arteries left the rete: A. ethmoidalis externa, A. ophthalmica externa, rami musculares and ramus pterygoideus. The rete mirabile of the maxillary artery in the lion provides the principal source of the blood for the brain; it also supplies the orbit.     

How many Layers has the Adventitia? – Structure of the Arterial Tunica Externa Revisited

Tunica adventitia or tunica externa is the outer layer of the blood vessel wall. It consists of connective tissue with vasa and nervi vasorum and plays a key role in vascular health. The aim of our study was to compare the wall layers beyond tunica media in arteries of different type and location. The following arteries of pig, dog and cat were processed histologically and analysed by light microscopy: aorta ascendens, arcus aortae, aorta thoracica, aorta abdominalis, arteria (a.) femoralis, a. tibialis cranialis, a. carotis communis, a. lingualis, a. basilaris, a. cerebralis media, a. testicularis and aa. jejunales. We found two layers of connective tissue outside the media: (1) a compact layer with many elastic fibres in muscular and few in elastic arteries and (2) an outer layer of loose connective tissue. The compact layer was missing in aorta ascendens, arcus aortae and intracranial vessels. Adventitial stripping removed only the loose connective tissue layer. In spite of the still present compact layer, stripped arteries were very flimsy. We suggest using the term ‘tunica externa’ for the compact connective tissue layer and ‘tunica adventitia’ for the outermost loose connective tissue layer as in other organs. The presence of the tunica externa differs between species, arteries and arterial side, as well as the removability of tunica adventitia and tunica externa by anatomical dissection.     

Morphological and immunocytochemical investigations on mast cells in porcine ureter

Morphological, morphometric, histochemical and immunocytochemical investigations on mast cells, located in the wall of ureter of 8 months aged pigs were performed. Mast cells were found in all three layers of ureteral wall, but their distribution was irregular and the number unequal. It was established that alcian blue (AB)-positive mast cells were significantly more than toluidine blue (TB)-positive mast cells. A statistically significant smaller number of both AB and TB-stained mast cells were observed in the tunica mucosa. The largest number of mast cells was found in the tunica muscularis. In the adventitia, mast cells were higher in number in the main connective tissue than in the connective tissue near the blood vessels. Mast cells stained with TB showed variably expressed gamma-metachromasia, which was best visible in those situated in the lamina propria of the mucosa. The prevailing parts of mast cells, however, were AB-positive after AB-safranin staining. This was mostly found in mast cells of the tunica muscularis and in mast cells of perivascular location in the tunica adventitia. Immunocytochemically, mast cells were found to be positive for histamine and vasoactive intestinal polypeptide in the muscle coat, and to histamine in the adventitia, as well. On the basis of obtained results it was presumed that the mast cells in porcine ureter most probably took part not only in keeping of local homeostasis, but played also an important role of mobility of smooth muscle cells in the middle layer of ureter on one hand, and, on the other, in the adventitial blood vessels.     

Histological and Histochemical Characterization of the Bovine Rete Ovarii through the Estrous Cycle and Gestation

The rete ovarii of cattle may be morphologically divided into the intraovarian rete, the connecting rete, and the extraovarian rete. The connecting rete may be subdivided into that portion which lies within the ovary proper and that portion that lies in the mesovarium. The portion of the connecting rete which lies in the mesovarium is connected to the infundibulum of the uterine tube by a patent tubo-retial communication.
Mitotic figures were observed in the epithelial cells of the rete ovarii during estrus, during metestrus, following superovulation, and in association with the cystadenomatous change which was observed in one ovary of an estrus cow. The epithelial lining of microcysts appeared to proliferate and produce material which filled the cysts. The occurrence of vesicles in the retial epithelium appeared more commonly during diestrus and gestation. The greatest amount of cells, cellular debris and amorphous luminal material was observed during anestrus, diestrus and gestation.     

Morphological Studies on the Peripheral Circulation of the Ovary in One‐Humped Camel (Camelus dromedarius)

Histological examination of the peripheral circulation of the ovary of 18 females of the one‐humped camel revealed a series of blood vessels with special structures. Throttle or occlusive artery was recorded in the ovarian zona vasculosa and in the cortex, and it showed an intimal cushion‐like thickening made up of intimal bolsters that formed of smooth muscle fibres and glomus cells. The smooth muscle cells of the tunica media and the tunica adventitia of throttle artery pursued a circumferential pattern. Anastomosis arteriovenosa included simple bridge‐like anastomotic vessels between arteria and venae, and glomus vessels of typical structure were demonstrated. Glomus organs were recorded in the ovary and were comprised of the tortuous glomus vessels and the related afferent and efferent vessels. Glomus cell complexes also were commonly occur at the cortex ovarii that possessed an extremely convoluted course with a hyperplastic wall and a narrow lumen. Atypical glomus vessels were demonstrated within the ovarian zona vasculosa, and the wall of these vessels was relatively thick and consisted of double tunica media with an intimal bolster. Some vessels contained an intimal bolster device of exclusively glomus cell structure (glomus bolster) with a tunica elastic interna demarcated it from the glomus cell media. Some venae represented several layers of longitudinally arranged smooth muscle fibres in the tunica media. Other venae showed wall with variable thickness. Venae with double muscular tunica media were recorded in the medulla. Some venae showed double internal elastic lamina. Also, venae with thick adventitia contained dispersed smooth muscle fibres were determined. Spirally oriented arteriole and venule were demonstrated within the cortex and medulla ovarii. Gestation sclerosis was demonstrated in ovarian zona vasculosa of pregnant females.     

余干乌骨鸡胃和小肠肥大细胞的分布特点

通过石蜡切片、改良甲苯胺蓝染色的方法对余干乌骨鸡主要胃肠道内的肥大细胞进行鉴定和分布特点分析。结果显示,在余干乌骨鸡的腺胃、肌胃、十二指肠、空肠和回肠管壁内皆有肥大细胞的分布,尤其是腺胃和肌胃内肥大细胞尤为丰富。肥大细胞主要位于胃肠道管壁内的黏膜固有层和肌层中,有些围绕着血管周围分布。黏膜下层极少有肥大细胞分布。外膜内无肥大细胞,但空肠外膜外附有的结缔组织中,脂肪细胞周围有肥大细胞分布。肥大细胞体积较大,多数呈卵圆形,有的细胞形态不规则,甚至有突起。胞质中含有紫红色颗粒。结果表明,余干乌骨鸡胃肠道管壁内具有丰富的肥大细胞,余干乌骨鸡胃肠道具有较强的抗病原微生物和抗寄生虫功能,肠道免疫屏障较为完善。同时,大量的肥大细胞在胃肠道内的分布可能与黑色素的生成具有相关性。     

山羊胚胎大动脉壁发育的组织学研究

本文应用光镜和透射电镜对山羊胚胎大动脉壁的发生发育过程进行了系统观察。结果表明：血管发生初期仅由一层内皮细胞构成。随着胚胎的发育，除毛细血管外，其它血管壁形成分层结构，形成内膜、中膜、外膜；胚胎大动脉内皮细胞胞质内存在着丰富的粗面内质网和游离核糖体，代谢是很活跃的；大动脉管壁的内弹性膜形成较晚，先产生小片段，然后呈连续带状；大动脉内膜和中膜内不含典型的成纤维细胞，在中膜内存在一种能产生胶原纤维的细胞，其结构类似于平滑肌细胞。     

成年皖西白鹅生殖系统ghrelin的免疫组化定位

为了研究皖西白鹅生殖系统内是否有产生Ghrelin细胞分布，应用免疫组化SABC法并结合DAB显色技术，结果：①在卵巢的生长卵泡中，均有ghrelin免疫阳性细胞，尤其在生长卵泡细胞的颗粒层更为明显；闭锁卵泡的卵泡外腺细胞也呈现ghrelin免疫阳性反应；②在输卵管五段的粘膜层中均观察到ghrelin免疫阳性细胞，其中，漏斗部细胞着色最深，数量最多，膨大部细胞反应最微弱，峡部、子宫部和阴道部ghrelin免疫反应介于二者之间，肌层和外膜均未见ghrelin表达。结论：产生Ghrelin的细胞在成年皖西白鹅卵巢和输卵管中均有广泛的分布，揭示Ghrelin可能调节生殖功能。     

Microscopical and Ultrastructural Studies of the Renal Artery in Domestic Swine

Both renal arteries from six, 8-month old, Camborow hybrid pigs were examined in histological, semithin and ultrathin sections. It was established that the membrana elastica interna showed an expressed degree of wrinkliness. In certain sections, sometimes occupying 20% of the diameter of a cross-section, its curves were considerably higher and wider than those in the remaining part. The inner elastic membrane in these sections was cleaved in two layers. Estates of lengthways-situated smooth muscle cells of an elliptical form were located in the middle shell (tunica media). Furthermore, a great quantity of mast cells were found in the middle shell. The electron-microscopic observations showed that their granules had various sizes and shapes. The outer shell (tunica adventitia) had an irregular thickness. In some parts, a few elastic fibres entered the middle shell. They had a tuft-like shape with a wedge-like or elongated configuration, and were situated among the layers of smooth-muscle cells.     

Immunohistochemical demonstration of myoid cells in the testis and its excurrent ducts in the domestic fowl

(1) Immunohistochemical methods and three antibodies (against actin, desmin and smooth muscle actin) were used to demonstrate the myoid cells in the domestic fowl testis and its excurrent ducts. (2) A positive reaction to actin, smooth muscle actin and desmin was found in the myoid cells of peritubular tissue of the testis and in rete testis, ductuli efferentes and ductus epididymidis. (3) In the testis myoid-reactive cells form a single layer. In the rete testis, ductuli efferentes and the ductus epididymidis reactive myoid cells form a main component of the stroma. (4) Positive reaction to actin, smooth muscle actin and desmin was also observed in the myoid cells of the tunica albuginea and in the wall of blood vessels in the testis and epididymis, indicating a contractile function for the testicular capsule.     

Morphological features of the spermatic cord in the musk shrew (Suncus murinus) with special reference to extratesticular Leydig cells

Morphological features of the testicular artery and vein in the spermatic cord of the musk shrew (Suncus murinus) were evaluated by light microscopy, transmission electron microscopy, corrosion cast technique combined with scanning electron microscopy and immunohistochemistry. The vascular architecture in the spermatic cord of the musk shrew was simple. The testicular artery in the musk shrew was straight and accompanied by 1 to 3 branches of testicular vein. The testicular vein was also straight and anastomosed with each other in some points along its length, but it did not form a delicate pampiniform plexus. In the middle and distal portions of the spermatic cord, the tunica adventitia of the artery and vein was joined together to form a single connective tissue septum. Clusters of cells were found in this connective tissue septum in the middle portion of the cord. These cells were located close to the arterial wall and nerve endings, but they did not appear inside of neurium. They showed several typical characteristics similar to Leydig cells, and they were positive for 3beta hydroxysteroid dehydrogenase (HSD) antibody. Ultrastructural and immunohistochemical studies also indicated that the cells in cluster found in the vascular wall of the musk shrew spermatic cord may be equivalent to Leydig cells in testes. These extratesticular Leydig cells had characteristics of the active steroid-producing cell and seemed to be another source of testosterone.