Bronchial blood flow

Parsons GH, Kramer GC, Link DP, Lantz BMT, Gunter RA, Green JF, Cross CE. Studies of reactivity and distribution of bronchial blood flow in sheep. Chest 1985 87(suppl 5) 182s. 

Kelly L, Kolbe J, Mitzner W, Spannhake EW, Bromberger-Bamea B, Menkes H. Bronchial blood flow affects recovery from constriction in dog lung periphery. J Appl Physiol 1986 60 1954 1959. 

In addition to these classic responses, activation of sensory nerves can cause an increase in bronchial blood flow (8), bronchomotor tone (1), mueous secretion (9-12), and ciliary beat frequency (13), and possibly an increase of transepithelial fluid transport (14,15). In concert, these effects on the components of the mucociliary transport system are likely to cause an increase in mucoeiliary... 

All of the foregoing cardiovascular and ventilatory and respiratoiy responses—namely, apnea followed by tachypnea, bradycardia, and increased bronchial blood flow, as well as systemic hypotension—observed in the pulmonary chemoreflex are characteristic of an anaphylactic reaction (31). An example of the cardiopulmonary responses to an inhaled allergen in a spontaneously breathing dog is shown in Figure 5. There is an increase in transpulmonary pressure indicative of an increase in airways resistance and a decrease in dynamic compliance. There is a marked apnea followed by tachypnea, a marked bradycardia and hypotension. Albeit, there may be some compensatory increase in heart rate, the induced hypotension persists. This hypotension is probably, partly, mediated by the induction of nitric oxide (NO) through the parasympathetically induced activation of nitric oxide synthase (32,33). 

N.A. Pinus albicaulis Engelm. P. contorta Dougl. ex. Loud. P. mugo Turra var. pumilio P. palustris Mill. P. strobus L. Bishomophinolenic acid, resins, mallol, bomeol acetate, tannins, vitamin A, vitamin C, galactose, alpha-pinenes, beta-pinenes, anthocyanin.8102 Relieve fever, bronchial and nasal congestion, improve blood flow. Anthocyanin from bark has antioxidant activity, inhibits the enzymes that cause inflammation. 

Besides neuropeptides, nitric oxide is an inflammatory mediator in the airways, which is also a vasodilator and a neurotransmitter. Nitric oxide is produced by the enzymatic action of nitric oxide synthetase on L-arginine. Airways contain this enzyme in three different forms, two of which termed neuronal and endothelial nitric oxide synthetase are constitutive whereas the third form called inducible nitric oxide synthetase is inducible. The inflammatory cytokines including IL-1 and TNF-a augment the expression of inducible nitric oxide synthetase in human airway epithelial cells. Nitric oxide causes bronchodilation as a result of the relaxation of bronchial smooth muscles. It has also been suggested that nitric oxide is the neurotransmitter of the inhibitory NANC bronchodilation. The detrimental effects of nitric oxide include airway inflammation and vasodilation. It causes airway edema by increasing the erudition of plasma due to increased blood flow to postcapillary venules. The increased blood flow may also contribute to an increased mucus secretion. The role of nitric oxide in inflammatory responses has not yet been established. 

Bradykinin 87 and kallidin (Lys-bradykinin-decapeptide), which are split off from the kininogen in the plasma by trypsin and kallikrein respectively (Fig. 10), hardly differ in their pharmacological activity. The most important effect of the kinins is a dilation of the peripheral vessels, which leads to an improved blood flow, in the kidneys for example, and therefore increases diuresis. By acting on the formation of angiotensin II, kinins can contribute to the regulation of blood pressure. Moreover, kinins cause a contraction of the bronchial muscle. 

Smooth muscle contraction. Affected are blood pressure, blood flow, the degree of bronchial constriction, and uterine contraction. 

Labetalol is less likely to increase airways resistance in patients with bronchial asthma or to reduce peripheral blood flow. However, it can produce postural hypotension (SEDA-3, 166-7), and paresthesia of the scalp (1,2) and perioral numbness (3) have been described. 

Bronchial constriction, especially in patients with asthma Reduced pulmonary blood flow and increased pulmonary blood pressure... 

Magno, M.G. and Fishman, A.P. (1982). Origin, distribution, and blood flow of bronchial circulation in anesthetized sheep. J. Appl. Physiol. 53, 272-279. 

There is also a high-pressure systemic blood delivery system to the bronchi that is completely independent of the pulmonary low-pressure ( 3330 N/m ) circulation in healthy individuals. In diseased states, however, bronchial arteries are reported to enlarge when pulmonary blood flow is reduced, and some arteriovenous shunts become prominent [West, 1977]. 

In the 1960s two types of receptors that are part of the natural regulatory system for heart rate were discovered and named beta-receptors. The beta-1 receptors are located primarily in the heart—stimulation of these sites speeds up the rate at which the heart beats. The beta-2 receptors are located in the peripheral blood vessels and the bronchial tubes. Stimulation of the beta-2 receptors relaxes muscle fibers, opening up the blood vessels and bronchial tubes so that blood flows more easily, making it easier to breathe deeply and quickly. These receptors are stimulated by the natural hormones epinephrine and norepinephrine during the fight-or- light response (Section 17.5). 

Long WM, Sprung CL, El Fawal H, Yerger LD, Eyre P, Abraham WM, Wanner A. Effects of histamine on bronchial artery blood flow and bronehomotor tone. J Appl Physiol 1985 254-261. 

Hi-receptors mainly mediate the constriction of large and relaxation of small blood vessels, contractions of the bronchial, intestinal and uterine smooth muscle and contractions of vascular endothelial cells with the result of an increased capillary permeability. The lymphatic flow is augmented by Hi-receptor stimulation. H2-receptor stimulation induce a dilatation of pulmonary arteries, a positive inotropic and chronotropic effect on the heart and an increased glandular secretion, especially in the mucosa of the stomach. 

Bronchodilation Human bronchial muscle vitro is known to be sensitive to PGE s. In preliminary studies PGEx (or the less irritating triethanolamine salt) given as an aerosol had no effect on resistance to air flow in normal subjects, but reduced resistance in asthmatic subjects with essentially no effects on ECG, blood pressure or pulse rate. ... 

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