Common carotid artery

Inverse association. + = Positive association. 0 = No association. CHD = coronary heart disease. CVD = cardiovascular disease. Ml = myocardial infarction. IMT = intima media thickness. CCA-IMT = common carotid artery intima media thickness. LDL = low-density lipoprotein. 

Carotenoids and cardiovascular diseases — Numerous epidemiological studies aimed to study the relationship of carotenoids and cardiovascular diseases (CVDs) including coronary accident risk and stroke. It appeared then that observational studies, namely prospective and case-control studies, pointed to a protective effect of carotenoids on myocardial infarct and stroke, but also on some atherosclerosis markers such as intima media thickness (IMT) of the common carotid artery (CCA) and atheromatous plaque formation. 

Chemoreceptors. The peripheral chemoreceptors include the carotid bodies, located at the bifurcation of the common carotid arteries, and the aortic bodies, located in the aortic arch. These receptors are stimulated by a decrease in arterial oxygen (hypoxia), an increase in arterial carbon dioxide (hypercapnia),... 

The peripheral chemoreceptors include the carotid and aortic bodies. The carotid bodies, which are more important in humans, are located near the bifurcation of the common carotid arteries. The aortic bodies are located in the arch of the aorta. The peripheral chemoreceptors respond to a decrease in P02/ an increase in PC02, and a decrease in pH (increase in H+ ion concentration) of the arterial blood. 

Branches of the aortic arch. Variation in the pattern of origin, a and b, Common pattern c and d, left common carotid artery from the innominate (long and short stem) e, separate origin of a thyreoidea ima artery / independent origin of a left vertebral. From Barry J. Anson, Atlas of Human Anatomy, p. 197. 

Figure 14.3 Integration plot of the initial uptake of [3H]adenosine by the retina after intravenous administration (A) and retinal uptake index (RUI) of [3H]adenosine and [3H]D-mannitol (B). A [3H]Adenosine (10 //.Ci/head) was injected into the femoral vein. B A test compound, [3H]adenosine or [3H]D-mannitol (10 //Ci/head), and a reference compound, [14C]n-butanol (0.1 //Ci/head), were injected into the common carotid artery in the presence or absence of 2 mM inhibitors. p < 0.05, significantly different from the control. Data from Biochimica et Biophysica Acta, 1758, Nagase et al., Functional and molecular characterization of adenosine transport at the rat inner blood-retinal barrier. 13-19, 2006, with permission from Elsevier.

In brief, the rats are anesthetized, followed by an injection of 0.2 mL of the test solution into the common carotid artery. The injection solution consists of a HEPES buffered Ringer s solution (containing 141 mM NaCl, 4 mM KC1, 2.8 mM CaCl2, and 10 mM HEPES, pH 7.4) which contains both the test substrate (e.g., a [3H]-labeled compound, about 10 /xCi) and a reference compound, which is highly extracted by the tissue (e.g., 0.1 /xCi [14C]n-butanol) in the presence or absence of transport inhibitors. If a [14C]-labeled compound is used as a test substrate, [3H]H20 can be selected as a reference compound. Rats are decapitated at 15 s after injection and the retina is removed. The retina is dissolved in 2 N NaOH and subsequently neutralized with 2 N HC1. The radioactivity is measured by liquid scintillation spectrometry. The RUI value, an index of the retinal distribution characteristics of the [3H] test substrate, is estimated using the following relationship ... 

Figure 2.4. In vivo measurement of blood-brain barrier (BBB) permeability, (a) Internal carotid artery perfusion technique (i) in the rat. Other branches of the carotid artery are ligated or electrically coagulated (o, occipital artery p, pterygopalatine artery). The external carotid artery (e) is cannulated and the common carotid artery (c) ligated. Perfusion time may range from 15 s to 10 min, depending on the test substance. It is necessary to subtract the intravascular volume, Vo, from (apparent volume of distribution), to obtain true uptake values and this may be achieved by inclusion of a vascular marker in the perfusate, for example labelled albumin. Time-dependent analysis of results in estimates of the unidirectional brain influx constant Ki (pi min which is equivalent within certain constraints to the PS product. BBB permeability surface area product PS can be calculated from the increase in the apparent volume of distribution Vd over time. Capillary depletion, i.e. separation of the vascular elements from the homogenate by density centrifugation, can discriminate capillary uptake from transcytosis. (b) i.v. bolus kinetics. The PS product is calculated from the brain concentration at the sampling time, T, and the area under the plasma concentration-time curve, AUC.

In the final study to be mentioned in regard to the possible penetration of pyrldinium oximes into brain, anesthetized, atropi-nized cats were given intravenous injections of sarin at 27/tg/kg. 12 Thirty minutes later, to allow clearance of unreacted sarin from the tissues, some cats received saline injections into one common carotid artery and others received similar injections of 1 at 15 mg/kg. The cholinesterase activity of cerebral cortex was measured. In animals given 1, nearly 20% of the cholinesterase in their cerebral cortices that had been inhibited by sarin was calculated to have been reactivated by the oxime. 

Concentrations of lipoprotein(a) were measured in 51 patients taking long-term carbamazepine, phenobarbital, phenytoin, or valproate and 51 age- and sex-matched controls (133). Lipoprotein(a) concentrations were above 450 pg/ml in 11 patients compared with only 4 controls, and the mean serum lipoprotein(a) concentrations were 330 and 169 pg/ml respectively. The epileptic patients also had a thicker intima media of the common carotid artery. These results suggest that patients taking antiepileptic drugs may be at a higher risk of atherosclerosis. 

Figure 8.1 Therapeutic effect of pomegranate juice on atherosclerotic lesion area in E° mice (A-C) or in patients with carotid artery stenosis (D and E). Thirty E° mice and 10 patients with severe CAS were supplemented with PJ concentrate (12.5 pL/mouse/day and 50 mL/day, respectively) for 9 weeks or for 1 year, respectively. Photomicrographs of typical foam cells from unsupplemented 4-month-old E° mice and from 6-month-old E° mice administered a placebo (B) or PJ (C) are presented. Mean ( SEM) effect of PJ consumption on human common carotid artery IMT (D) and end diastolic velocity (EDV) (E) are shown. = p < 0.01 (after vs. before PJ consumption).

Akin D, Gurdal H. Involvement of 5-HTm and 5-HT1D receptors in sumatriptan mediated vasocontractile response in rabbit common carotid artery. Br J Pharmacol 2002 136 177-182. 

Fig. 5.28. Radiogenic carotid stenosis. CE-MRA depicts atypi-cally located proximal h igh grade stenosis of the right common carotid artery...

CBF, Cerebral blood flow CCAo, common carotid artery occlusion cGMP, cyclic guanine monophosphate ICAM-1, intercellular adhesion molecule-1 ICAo, internal carotid artery occlusion MCAo, middle cerebral artery occlusion NAA, A-acetyl-aspartate NOS, nitric oxide synthase SD, Sprague-Dawley SH, spontaneously hypertensive SOD, superoxide dismutase TUNEL, transferase dUTP nick-end labeling. 

For determination of LVP, a Millar micro tip catheter (type PC 350) is inserted via the left common carotid artery into the left ventricle. LVEDP is measured on a high-sensitivity scale. From the pressure curve, dP/dtmax is differentiated and heart rate is counted. The LVP-signal also triggers a cardiotachometer. 

Rote et al. (1993, 1994) used a carotid thrombosis model in dogs. A calibrated electromagnetic flow meter was placed on each common carotid artery proximal to both the point of insertion of an intravascular electrode and a mechanical constrictor. The external constrictor was adjusted with a screw until the pulsatile flow pattern decreased by 25 % without altering the mean blood flow. Electrolytic injury to the intimal surface was accomplished with the use of an intravascular electrode composed of a Teflon-insulated silver-coated copper wire connected to the positive pole of a 9-V nickel-cadmium battery in series with a 250000 ohm variable resistor. The cathode was connected to a subcutaneous site. Injury was initiated in the right carotid artery by application of a 150 xA continuous pulse anodal direct current to the intimal surface of the vessel for a maximum duration of 3 h or for 30 min beyond the time of complete vessel occlusion as determined by the blood flow recording. Upon completion of the study on the right carotid, the procedure for induction of vessel wall injury was repeated on the left carotid artery after administration of the test drug. 

Guarini (1996) produced a completely occlusive thrombus in the common carotid artery of rats by applying an electrical current to the arte-... 

Chen SD, Zhou XD, Xu DL, Li GW, Tang QM, Xu XR (1991) Hemiparkinsonism in monkeys following unilateral common carotid artery infusion of MPTP. A study of behavior, biochemistry and histology. Chin Med J (Engl) 707 758-763. 

The internal carotid artery starts as the carotid sinus at the bifurcation of the common carotid artery at the level of the thyroid cartilage. It runs up the neck, without any branches, to the base of the skull where it passes through the foramen lacerum to enter the carotid canal of the petrous bone. It then runs through the cavernous sinus in an S-shaped curve (the carotid siphon) pierces the dura and exits just medial to the anterior clinoid process. It then bifurcates into the anterior cerebral artery and the larger middle cerebral artery. 

Muscular branches of the vertebral artery in the neck. At positions distal to a vertebral obstruction, these muscular branches may receive blood retrogradely from occipital and ascending pharyngeal branches of the external carotid artery, or from the deep and ascending cervical arteries. In addition, anastomoses can develop between branches of the subclavian artery and external carotid artery when the common carotid artery is obstructed. 

The subclavian artery can be damaged by a fractured clavicle or a cervical rib, with later embolization up the vertebral arteries or even up the right common carotid artery (Prior et al. 1979). 

Tenderness of the branches of the external carotid artery (occipital, facial, superficial temporal) points towards giant cell arteritis. Tenderness of the common carotid artery in the neck can occur in acute carotid occlusion but is more Ukely to be a sign of dissection, or arteritis. Absence of several neck and arm pulses in a young person occurs in Takayasu s arteritis (Ch. 6). Delayed or absent leg pulses suggest coarctation of the aorta or, much more commonly, peripheral vascular disease. Other causes of widespread disease of the aortic arch are atheroma, giant cell arteritis, syphihs, subintimal fibrosis, arterial dissection and trauma. 

Fig. 12.3. A color-flow Doppler ultrasourid of the carotid bifurcatlori showirig a plaque (arrow) at the origiri of the Iriterrial carotid artery (ICA) arid the resulting stenosis. ECA, external carotid artery CCA, common carotid artery. (See the color plate section.)...

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