Meningeal arterial patterns in great apes: Implications for hominid vascular evolution

Arterial meningeal patterns were observed for 100 hemispheres from great ape endocasts (Pan paniscus, Pan troglodytes, Gorilla gorilla, and Pongo pygmaeus). Eight patterns emerged based on the relative contributions to the walls and dura mater of the middle part of the braincase of meningeal arteries that stem from two sources. These arteries enter the braincase through either the orbit (delivering blood from the internal carotid artery) or through the base of the middle cranial fossa (via the middle meningeal artery whose blood comes from the external carotid artery). The three genera of apes manifest different frequencies of the eight, patterns, with orangutans highly dependent on orbital meningeal arteries at one extreme, and chimpanzees showing the greatest reliance on the middle meningeal artery at the other. As was the case in an earlier study of rhesus monkeys, there is a trend across the two genera of African apes for increased mean cranial capacity to be associated with increased reliance on the internal carotid artery for supplying the middle portion of the braincase. However, unlike the case for macaques, this trend does not reach statistical significance in African apes. Because it is rare for humans to manifest significant arterial contributions from the orbit to the middle cranial fossa, the comparative data on monkeys, apes, and humans suggest that, during the course of vascular evolution in Homo, the middle meningeal artery eventually took over supply of the entire middle cranial fossa. This hypothesis should be tested in the hominid fossil record. Earlier work on meningeal arterial patterns in apes has traditionally relied on Adachi's system that was determined from humans and focuses on the origin of the middle branch of the middle meningeal artery. As a result, the extensive orbital contributions to the middle portion of the braincase that characterize apes were not recognized and the eight patterns described in this paper were often erroneously assigned to the three patterns that adequately describe only humans. Adachi's system should therefore be abandoned for nonhuman primates and early hominids. A correct understanding of meningeal arterial evolution cannot be achieved until the orbital contributions to the meningeal arteries are recognized and incorporated into an evolutionary study that spans from apes to fossil hominids to living people. © 1993 Wiley-Liss, Inc.     

Anatomy of the arteries of the head in the domestic fowl

The anatomy of the cephalic arterial system in the fowl was studied in 24 specimens by means of latex-injected preparations and by dissection. Branches of the external carotid artery supply the extracranial regions. The vertebral arteries unite with the occipitals and have no major communications with the encephalic system. Blood can reach the brain directly from the internal carotid artery and indirectly by way of the extensive cerebral-extracranial anastomoses; especially prominent are those to the palatine and sphenomaxillary arteries from the maxillary and facial branches of the external carotid artery. A large external ophthalmic artery supplies the temporal rete and eye musculature, and an internal ophthalmic artery links the rete and the cerebral vessels. The circle of Willis is incomplete both anteriorly and posteriorly; the anterior cerebral arteries do not unite and the basilar artery is generally asymmetrical in origin. The basilar artery tapers caudally and is continued as the ventral spinal artery.     

Homeobox gene hoxa3 is essential for the formation of the carotid body in the mouse embryos

Homeobox gene Hoxa3 is strongly expressed in the third pharyngeal arch and pouch. We found that Hoxa3 homozygous null mutant mice had the lack of the carotid body. In all late-term mutant embryos examined (n = 10), no carotid body was present. The carotid body rudiment is formed in the wall of the third branchial artery, which develops into the common carotid artery and the first part of the internal carotid artery. The symmetrical patterns of the third, fourth, and sixth arch arteries were observed in wild-type littermates at embryonic day (E) 10.5-12.5. In Hoxa3 homozygous mutant embryos, however, the third arch artery began to degenerate at E10.5 and almost disappeared at E11.5. Furthermore, the bifurcation of the common carotid artery at the normal position, i.e., at the upper end of the larynx, was never detected in the mutant embryos at E16.5-E18.5. The common carotid artery of the homozygous mutants was separated into the internal and external carotid arteries immediately after its origin. Thus, the present study evidenced that the absence of the carotid body in Hoxa3 homozygous mutants is due to the defect of development of the third arch artery, resulting in malformation of the carotid artery system. During fetal development, the carotid body of mice is in close association with the superior cervical ganglion of the sympathetic trunk. The superior cervical ganglion rather showed hypertrophic features in Hoxa3 homozygous mutants lacking the carotid body.     

Structure and sympathetic innervation of the intracranial arteries in the giraffe (Giraffa camelopardalis)

Fluorescence histochemistry discloses that the carotid rete mirabile in the giraffe has a poor sympathetic innervation. In contrast, the efferent artery of the rete (internal carotid artery) and the cerebral arteries show moderate sympathetic innervation. A certain degree of regional variability was noted in which the rostral arteries (anterior and middle cerebral) receive more sympathetic nerves than the caudal (posterior communicating and basilar) arteries. The sympathetic nerves on the giraffe cerebral vessels may constitute part of a host of mechanisms by which regional blood flow to the brain is regulated. Conversely, the paucity of sympathetic innervation of the carotid rete mirabile may indicate that this structure does not play an active role in vasoconstrictor responses during postural changes of the head.     

Corrosion anatomical studies of the rete mirabile and the brain basal vessels of pygmy goats

The rete mirabile and cerebral arteries represent a multifunctional system. Age-associated morphological changes at the rete mirabile and major cerebral arteries were observed in pygmy goats. The most important arteries for cerebral circulation are the ramus rostralis and ramus caudalis of the maxillary artery. The persistence of the internal carotid artery ( = 80%) in newborn and adult goats is a quite new result. The thermoregulatory function of head fighting-mammals with a large frontal sinus and the mechanical function of the rete mirabile were discussed.     

Cranial morphology of Aegyptopithecus and Tarsius and the question of the tarsier-anthropoidean clade

New crania of the Oligocene anthropoidean Aegyptopithecus provide a test of the hypothesized tarsier-anthropoidean clade. Three cranial characters shared by Tarsius and some modern anthropoideans (apical interorbital septum, postorbital septum, "perbullar" carotid pathway) were examined. 1) An apical interorbital septum is absent in Aegyptopithecus. A septum does occur in Galago senegalensis (Lorisidae) and Microcebus murinus (Cheirogaleidae), so the presence of a septum is not strong evidence favoring a tarsiiform-anthropoidean clade. 2) In Aegyptopithecus and other anthropoideans, the postorbital septum is formed mainly by a periorbital flange of the zygomatic that extends medially from the lateral orbital margin onto or near the braincase. The postorbital plate of Tarsius is formed by frontal and alisphenoid flanges that extend laterally from the braincase to the zygomatic's frontal process, which is not broader than the postorbital bars of other prosimians. Periorbital flanges evolved in Tarsius for support or protection of the enormous eyes, as suggested by the occurrence of maxillary and frontal flanges that cup portions of the eye but do not separate it from temporal muscles. 3) The internal carotid artery of Aegyptopithecus enters the bulla posteriorly and crosses the anteroventral part of the promontorium. The tympanic cavity was probably separated from the anteromedial cavity by a septum stretching from the carotid channel to the ventrolateral bullar wall. In Tarsius, the carotid pathway is prepromontorial, and a septum stretches from the carotid channel to the posteromedial bullar wall. Quantitative analyses indicate that anterior carotid position has evolved because of erect head posture. The cranium of Oligocene anthropoideans thus provides no support for the hypothesized tarsier-anthropoidean clade.     

The primitive course of the internal carotid artery in mammals.

In all recent mammals the internal carotid artery at the level of the auditory capsule is derived from the embryonic dorsal aorta. In adults of various groups, the artery lies in positions which are classified as medial or promontory. It is shown that these character states arise by a process of differential growth affecting the relative positions of the dorsal aorta and the cochlear promontory. There is no evidence for separate vessels in the embryo which could give rise to non-homologous internal carotid arteries in the two positions. It follows that the concept of a primitive mammalian morphotype with both a medial and a promontory internal carotid artery in the same individual presents a formidable embryological problem. It is recommended that, in the absence of supporting evidence, the widespread current taxonomic and palaeontological use of this hypothetical morphotype should be regarded with suspicion.     

早期颈内动脉支架置入对动脉粥样硬化脑梗患者血清Lp-PLA2和Hcy水平的影响

摘要 目的：探讨早期颈内动脉支架置入（carotid artery stenting,CAS）对动脉粥样硬化脑梗死患者血清脂蛋白相关磷脂酶2（lipoprotein-associated phospholipase 2,LP-PLA2）和同型半胱氨酸（Homocysteine,Hcy）水平的影响。方法：选择2018年8月到2021年4月在在西安交通大学第一附属医院诊治的颈动脉重度狭窄性脑梗死患者86例作为研究对象,根据治疗方法将患者分为早期CAS组与对照组各43例,对照组给予药物保守治疗,2周后脑梗死稳定后再给予手术,CAS组在对照组基础上治疗3~5 d后给予颈内动脉支架置入治疗,检测两组患者血清Lp-PLA2和Hcy水平变化情况。结果：CAS组治疗后7 d的总有效率为97.7 %,高于对照组的86.0 %（P<0.05）。CAS组治疗后7 d的高灌注综合征、脑出血、低血压、心动过缓等并发症发生率为4.7 %,对照组无出现高灌注综合征、脑出血、低血压、心动过缓等并发症,对比差异无统计学意义(P>0.05)。两组治疗后7 d的颈内动脉相对脑血流量与脑血容量高于治疗前(P<0.05),CAS组高于对照组(P<0.05)。两组治疗后7 d的血清Lp-PLA2、Hcy含量低于治疗前（P<0.05）,CAS组低于对照组（P<0.05）。结论：早期颈内动脉支架置入在动脉粥样硬化脑梗死患者的应用能抑制Lp-PLA2、Hcy的表达,改善患者的血流动力学变化,从而促进提高治疗效果,在临床上的应用具有很好的安全性。     

Proposition of an outflow boundary approach for carotid artery stenosis CFD simulation

The purpose of this study was to propose an innovative approach of setting outlet boundary conditions for the computational fluid dynamics (CFD) simulation of human common carotid arteries (CCAs) bifurcation based on the concept of energy loss minimisation at flow bifurcation. Comparisons between this new approach and previously reported boundary conditions were also made. The results showed that CFD simulation based on the proposed boundary conditions gave an accurate prediction of the critical stenosis ratio of carotid arteries (at around 65%). Other boundary conditions, such as the constant external pressure (P = 0) and constant outflow ratio, either overestimated or underestimated the critical stenosis ratio of carotid arteries. The patient-specific simulation results furthermore indicated that the calculated internal carotid artery flow ratio at CCA bifurcation (61%) coincided with the result obtained by clinical measurements through the use of Colour Doppler ultrasound.     

兔血管外膜对血管重构及收缩功能影响的初步观察

本文研究血管外膜在血管重塑及功能调控中的作用。实验采用在体去除兔颈动脉外膜的方法,于术后即刻、1周及2周取出动脉作组织学、免疫组织化学染色及血管反应性测定。结果显示：(1)去除颈动脉局部外膜对内皮及中层平滑肌无明显损伤;(2)去除外膜后血管平滑肌细胞增殖,并有新生内膜形成;(3)与对照例比较,去外膜侧血管对去甲肾上腺素的收缩反应在术后即刻及1周时减弱(P＜0．05)。上述研究结果提示：去除动脉外膜可导致血管内膜增殖及血管平滑肌收缩功能的改变,表明外膜可能参与血管重塑及对血管功能的调控。     

Guttural pouches, brain temperature and exercise in horses

Selective brain cooling (SBC) is defined as the lowering of brain temperature below arterial blood temperature. Artiodactyls employ a carotid rete, an anatomical heat exchanger, to cool arterial blood shortly before it enters the brain. The survival advantage of this anatomy traditionally is believed to be a protection of brain tissue from heat injury, especially during exercise. Perissodactyls such as horses do not possess a carotid rete, and it has been proposed that their guttural pouches serve the heat-exchange function of the carotid rete by cooling the blood that traverses them, thus protecting the brain from heat injury. We have tested this proposal by measuring brain and carotid artery temperature simultaneously in free-living horses. We found that despite evidence of cranial cooling, brain temperature increased by about 2.5 degrees C during exercise, and consistently exceeded carotid temperature by 0.2-0.5 degrees C. We conclude that cerebral blood flow removes heat from the brain by convection, but since SBC does not occur in horses, the guttural pouches are not surrogate carotid retes.     

Extravasation of pertechnetate in cranial extracerebral tissues during first pass across the cerebral vasculature

By evaluating regional cerebral first pass curves following Pertechnetate administration in common, internal and external carotid artery, it has been shown that about 20% of the injected dose of Pertechnetate extravasates in cranial extracerebral tissues during the first pass. This extravasation may lead to an overestimation of about 1 sec in the determination of regional cerebral mean transit time by intravenous radionuclide Angiography.     

The anatomy and phylogenetic significance of the carotid arteries and nerves in strepsirhine primates

The internal carotid artery in lorisiform primates was identified on the basis of its close association with the internal carotid nerve (postsynaptic sympathetic trunk). An atrophic vessel in the lorisine Arctocebus resembles the internal carotid artery of Lemur in that it enters the tympanic bulla and promontory tube closely associated with the internal carotid nerve. According to this criterion of homology, the enigmatic lorisiform extrabullar carotid artery is not homologous with the internal carotid (promontory) artery of lemuriform primates or the medial internal carotid artery of the dog. Hypotheses about strepsirhine evolution must take these morphological facts into account.     

CAS和CEA治疗颈内动脉重度狭窄疗效及对脑血流量、血清miR-145、IGF1R的影响

目的:探讨颈动脉支架植入术(CAS)和颈动脉内膜剥脱术(CEA)治疗颈内动脉重度狭窄疗效及对脑血流量、血清miR-145、胰岛素样生长因子1受体(IGF1R)的影响。方法:回顾性分析2018年1月至2019年12月我院收治的100例颈动脉重度狭窄患者的临床资料,按照手术方式不同分为A组和B组,每组50例,A组给予CAS治疗,B组给予CEA治疗。比较两组围术期情况、脑血流量、血清miR-145、IGF1R、简易精神状态检查表(MMSE)量表、蒙特利尔认知评估量表(MoCA)的变化,并比较术后并发症、再狭窄率及死亡率。结果:两组患者手术时间、术中失血量、术后机械通气时间、ICU停留时间、住院时间比较,差异无统计学意义(P>0.05);术后3个月时,两组脑血流量指标相对达峰时间(rTTP)、相对平均通过时间(rMTT)、相对脑血容量(rCBV)、相对脑血流量(rCBE)、血清miR-145、IGF1R、MMSE量表、MoCA量表评分比较差异均无统计学意义(P>0.05);术后30 d内,两组心动过缓、心肌酶谱升高、高灌注综合征、局部血肿、颈动脉急性闭塞比较差异无统计学意义(P>0.05),A组脑卒中、低血压发生率明显高于B组,B组高血压发生率明显高于A组(P<0.05);术后1年时,两组患者死亡率、再狭窄率比较差异无统计学意义(P>0.05)。结论:CAS和CEA治疗颈内动脉重度狭窄患者的疗效相似,均可有效改善脑血流量,调节血清miR-145、IGF1R水平的表达,促进认知功能恢复,但CAS术后脑卒中、低血压发生率更高,CEA术后高血压发生率更高。     

A histochemical study on the innervation of the cerebral blood vessels in bats

Summary The adrenergic and cholinergic nerves innervating the cerebral blood vessels of four species of Japanese chiropterids (Rhinolophus ferrumequinum, Murina leucogaster, Vespertilio superans and Miniopterus Schreibersi) have been investigated using specific histochemical techniques. In all these species of bats arteries of the internal carotid system are poorly developed, whereas those of the vertebro-basilar system are well developed. The adrenergic and cholinergic nerves innervating these cerebral arteries, however, all originate from the stem nerve bundles entering the cranial cavity along the internal carotid artery. Both nerve plexuses are among the densest of any vertebrate species so far investigated. Adrenergic nerve plexuses are usually composed of complicated meshworks of fine fibres, while cholinergic ones are composed of rather longitudinally arranging meshworks of both thick and thin fibres, exhibiting a very high acetylcholinesterase activity. Small parenchymal arteries and arterioles are also dually innervated by adrenergic and cholinergic nerve fibres of peripheral origin. Intracerebral capillaries, on the other hand, are in several places directly connected with both adrenergic and cholinergic fibres of parenchymal origin. Capillaries in the cerebral and cerebellar cortices, diencephalon and cochlear nucleus in V. superans exhibit a heavy non-nervous acetylcholinesterase activity in their walls, but in R.ferrumequinum and M. schreibersi, the response is weak or negative, except for that in the cochlear nucleus.     

中华蟾蜍颈动脉腺的组织学结构

2005年10月～2006年5月,用组织学技术研究中华蟾蜍颈动脉腺结构。结果表明,颈动脉腺位于外颈动脉基部,圆球形,深红色至棕褐色。组织结构显示：颈动脉腺的外壁是动脉管壁的延续,包括外膜、中膜和内膜。整个外壁厚薄不均。颈动脉腺的最大特点是中膜和内膜并不像一般血管形成环圈状,而是从不同部位向管腔突出延伸、相互连接构成大小不一、形状各异、迂回曲折的网状血管。管腔大者,管壁厚,弹性纤维、平滑肌纤维多,内膜靠腔面内皮细胞多成立方状,细胞核端位近圆形;管腔小者,管壁薄,弹性纤维、平滑肌纤维少,内皮细胞扁平、排列稀疏,胞核长梭形;一些区域管径极小,管壁极薄,成为开放的血窦,只允许一个血细胞通过。网状管壁间有密集成团的大型类上皮细胞等细胞分布。据结构推测中华蟾蜍颈动脉腺有调节血压等功能。     

Middle ear morphology of Lemur variegatus. Some implications for primate paleontology.

The middle ear morphology of Lemur variegatus, a strepsirhine primate, is described. Although no promontory branch of the internal carotid artery appears, there is a well-developed "promontory canal" containing a nerve trunk. This structure, which is previously undescribed in strepsirhines, is made up of the tympanic nerve and the internal carotid nerve. The implications of this discovery for paleontology, systematics, and future research are discussed.     

The persistent trigeminal artery and its topographical relations

The topographical relation of a persistent trigeminal artery (PTA) to neighboring structures was investigated. The vessel belongs to Saltzman's type I. It originates from segment C5 of the internal carotid artery and opens into the basilar artery, 8 mm before the bifurcation into the two posterior cerebral arteries. The 6th cranial nerve winds around the first part of the PTA which is situated within Parkinson's triangle.     

Distribution and origin of vasoactive intestinal polypeptide (VIP)-immunoreactive,acetylcholinesterase-positive and adrenergic nerves of the cerebral arteries in the bent-winged bat (Mammalia: Chiroptera)

Summary The overall distribution and origins of vasoactive intestinal polypeptide (VIP)-immunoreactive (IR), acetylcholinesterase (AChE)-positive and adrenergic nerves in the walls of the cerebral arteries were investigated in the bent-winged bat. VIP-IR and AChE-positive nerves innervating the bat cerebral vasculature appear to arise mainly from VIP-IR and AChE-positive cell bodies within microganglia found in the nerve bundle accompanying the sympathetic nerve bundle within the tympanic cavity. These microganglia, as well as the nerve bundle containing them, do not emit catecholamine fluorescence, suggesting that they are of the cranial parasympathetic outflow, probably the facial or glossopharyngeal one. The axons from VIP-IR and AChE-positive microganglia run intermingled with sympathetic adrenergic nerves in the same thick fiber bundles, and reach the cranial cavity through the carotid canal. In addition, some of the VIP-IR fibers innervating the vertebro-basilar system, at least the basilar artery, originate from VIP-IR nerve cells located in the wall of this artery.The supply of VIP-IR fibers to the bat major cerebral arteries is the richest among mammals that have been studied, and differs from other mammals in that it is much greater in the vertebro-basilar system than in the internal carotid system: plexuses of VIP-IR nerves are particularly dense along the walls from the posterior ramus to posterior cerebral and basilar arteries. Small pial and intracerebral arteries of the vertebro-basilar system, especially those of the posterior cerebral artery which supply most parts of the diencephalon and cerebrum, are also richly innervated by peripheral VIP-IR fibers. This pattern corresponds well with the innervation pattern of adrenergic and AChE-positive nerves.     

Comparative anatomical studies of thyroid and thymic arteries: I. Rat (Rattus norvegicus albinus)

The thyroid and thymic arteries were investigated in 50 male and 50 female rats. In more than 70% of the animals, on both sides the cranial thyroid artery forms a common trunk with the ascending pharyngeal artery. The caudal thyroid artery arises not from the deep cervical but from the pericardiacophrenic artery. It may be replaced, however, by a branch of some other artery, such as the brachiocephalic, subclavian, vertebral, or ascending cervical, suggesting a shift of its origin from the internal thoracic artery to the thyrocervical trunk as in man. All the thoracic lobes of the thymus are supplied directly by a thymic branch of the internal thoracic artery or indirectly by a branch of the pericardiacophrenic artery. More than half of the specimens have a cervical thymic lobe of variable size, which is supplied by a branch of the cranial thyroid, external carotid, and/or occipital arteries. Some of these thymic arteries, except those from the external carotid and occipital arteries, reach the thoracic lobe. The thoracic lobes lacking a cervical lobe may be supplied by the thymic branch arising only from the cranial thyroid artery. Other anomalous arteries supplying the thoracic lobe are derived from the superficial cervical and/or the right common carotid arteries. These results show that the thymic arteries of rats are basically similar to those of man, although they display a clear difference in their frequency and origin.