Vascular responses

Nasal vasculature may offer some insight into this question, though research to date has been equivocal. Nasal turbinate vessels can be classified as either capacitance vessels or resistive vessels. Capacitance vessels appear to vasodilate in response to infection while resistance vessels appear to respond to cold stimuli by vasoconstriction. Buccal vascular structures also respond to thermal stimuli but appear to respond principally to cutaneous stimuli. How pharyngeal and tracheobronchial submucosal vessels react to thermal stimuli is not known, though cold-induced asthma is believed to result from broncho-spasms caused by susceptible bronchial smooth muscle responding to exposure to cold dry air.- This asthmatic response suggests an inadequate vascular response to surface cooling. 

Cole, P. (1954). Respiratory mucosal vascular responses, air conditioning and thermoregulation./. Laryngol. Otol. 68, 613-622. 

Raynaud s phenomenon is an exaggerated vascular-response to cold temperature or emotional stress. Clinical symptoms are sharply demarcated color-changes in the skin of the digits. The underlying disorder consists of abnormal vasoconstriction of digital arteries and cutaneous arterioles due to a local defect in normal vascular responses. 

J10. Julou-Schaeffer, G., Gray, G. A., Fleming, I., Schott, C. C., Parratt, J. R., and Stoclet, J. C., Loss of vascular responsiveness induced by endotoxin involves L-arginine pathway. Am. J. Physiol. 259, H1038-H1043 (1990). 

Hopkins PN, Lifton RP, Hollenberg NK, Jeunematre X, Hallouin MC, Skuppin J, Williams CS, Dluhy RG, La-louel JM, Williams RR, Williams GH. Blunted renal vascular response to angiotensin II is associated with a common variant of the angiotensinogen gene and obesity. J Hypertens 1996 14 199-207. 

NK. Blunted renal vascular response to angiotensin II is associated with a common variant of the angiotensinogen gene and obesity. J Hypertens 1996 14 199-207. 

Despite their successful use for at least 20 years, the mechanisms by which they lower the blood pressure remain uncertain. Theories to explain the antihypertensive effectiveness of the diuretic agents have included a) alteration of sodium and water content on arterial smooth muscle, b) the induction of a decreased vascular response to catecholamines, c) a decrease in blood volume and total extracellular fluid volume, and d) a direct vasodilator action independent from the diuretic effect(12). 

Altered vascular responses When P2-receptors are blocked, the vasodilating effect of epinephrine is abolished, leaving the a-receptor-mediated vasoconstriction unaffected peripheral blood flow i - cold hands and feet . 

Histamine (B). Histamine is stored in basophils and tissue mast cells. It plays a role in inflammatory and allergic reactions (p. 72, 326) and produces bronchoconstriction, increased intestinal peristalsis, and dilation and increased permeability of small blood vessels. In the gastric mucosa, it is released from enterochromaffin-like cells and stimulates acid secretion by the parietal cells. In the CNS, it acts as a neuromodulator. Two receptor subtypes (G-pro-tein-coupled), H and H2. are of therapeutic importance both mediate vascular responses. Prejunctional H3 receptors exist in brain and the periphery. 

In animal studies, pigs exposed at 25, 50, and 100 ppm continuously for 6 days exhibited lethargy and a concentration-related depression of body weight gain. Concentrations greater than 50 ppm altered the pulmonary vascular response to endotoxins. 

The dorsal skin fold window model allows direct observation of tumor microvasculature (11). This model also permits longitudinal assessment of the tumor vascular response to therapy. An accurate systematic measurement of tumor blood vessels in the window model is the linear summation of blood vessels using Optimas software. This approach corrects for vascular dilation and hemorrhage. Quantification of red... 

In any blood vessel, the final integrated response to either neuronally released norepinephrine or to circulating epinephrine probably depends on the relative participation of at least four populations of a-adreno-ceptors postjunctional i- and az-adrenoceptors mediate constriction of vascular smooth muscle, while prejunctional and endothelial az-adrenoceptors mediate vasodilation. An understanding of the vessel vascular response to adrenomimetic drugs also must include the effects of drugs on adventitial innervation, smooth muscle, and other vascular factors that may be present. 

Patients with coronary artery disease are particularly challenging for anesthesia, since alterations in vascular responsiveness and myocardial function may put them at risk. In this respect, which statement correctly describes the cardiovascular action of an agent or agents that should be taken into account when planning anesthesia for such patients ... 

Williams JK, Adams MR, Herrington DM, Clarkson TB. Short-term administration of estrogen and vascular responses of atherosclerotic coronary arteries. J Am Coll Cardiol 1992 20(2) 452-7. 

Dietary Flavanols Biochemical Basis of Short-Term and Longer-Term Vascular Responses... 

The literature on vascular responses to dietary components [e.g., Fitzpatrick et al., 1995] has increased substantially in recent years. Short-term and long-term consumption of black tea was shown to reverse endothelial dysfunction in patients with coronary artery disease [Duffy et al., 2001]. On the acute shortterm time frame, which is taken here as the responses observed between 0 and 6 h, we demonstrated increases in flow-mediated dilation of the brachial artery upon intake of high-flavanol cocoa drink, but not of low-flavanol cocoa drink, in a crossover study [Heiss et al., 2003]. The effect of the flavanol-rich cocoa drink on flow-mediated dilation as well as the increase in circulating... 

As in the studies on tea [Duffy et al., 2001], a chronic longer-term vascular response was identified with high-flavanol cocoa, when the flavanol-containing beverage was administered repetitively over several days [Heiss et al., 2007], This effect was clinically characterized as continuously elevated baseline of flow-mediated dilation, on top of which the short-term effect was added on with every new dose this additive effect was at about the same magnitude as without the pretreatment. 

JAMs. Members of an immunoglobulin subfamily expressed by leukocytes, platelets, and endothelial cells, regulates leukocyte/platelet/endothelial cell interactions in the immune system, and promotes inflammatory vascular responses... 

Zidar I, Jackman J, Gmmon R, et al. Serial assessment of heparin coating on vascular response to a new tantalum stent [abstr]. Circulation 1992 89 1-185,... 

Zidar I, Virmani R, Culp S, et al. Quantitative histopathologic analysis of the vascular response to heparin coating of the Cordis stent [abstr], J Am Coll Cardiol 1993 I2 336A,... 

Furthermore, there is a direct correlation between the paclitaxel dose delivered to the artery and the vascular response when examined in the porcine coronary artery model. The slow-release formulation demonstrated patent lumen, struts covered by stable intima and re-endothelializa-tion with minimal fibrin, whereas the fast-release formulation resulted in noticeable fibrin accumulation, an indication of higher level of drug exposure to the arteries (Fig. 10). It should be noted that the 8.8% slow-release formulation is currently marketed as TAXUS SR and has demonstrated efficacy in clinical studies this is discussed in the next section. 

See color plate) Vascular response to slow-, moderate-, and fast-release formulations of paclitaxel in the porcine coronary artery model. Vascular response to 1 jAg/mm2 slow-, moderate-, and fast-release formulations in the porcine coronary artery model. Source. From Ref. 55. 

Spironolactone reportedly reduces vascular responsiveness to norepinephrine, so regional or general anesthesia should be used with caution in patients receiving spironolactone. 

Sandall, D. W Satkunanathan, N., Keays, D. A., et al. (2003) A novel a-conotoxin identified by gene sequencing is active in suppressing the vascular response to selective stimulation of sensory nerves in vivo. Biochemistry 42, 6904-6911. 

Kim, S., and Iwao, H. 2003. Stress and vascular responses mitogen-activated protein kinases and activator protein-1 as promising therapeutic targets of vascular remodeling. J Pharmacol Sci 91 77-181. 

Lavrijsen, A., Oestmann, E., Hermans, J., Bodde, H., Vermeer, B., and Ponec, M., Barrier function parameters in various keratinzation disorders transepidermal water loss and vascular response to hexyl nicotinate, Br. J. Dermatol., 129, 547, 1993. 

Mild bleeding disorder and altered vascular responses to TXA2 and arachidonic acid (Thomas et al. 1998). 

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