Perivascular pH and pial arterial diameter during bicuculline induced seizures in cats

1979 ◽  
Vol 382 (1) ◽  
pp. 81-85 ◽  
Author(s):  
W. Kuschinsky ◽  
M. Wahl
Keyword(s):  
2020 ◽  
Vol 1 ◽  
pp. 247
Author(s):  
Derek Afflu ◽  
Dylan D. McCreary ◽  
Nolan Skirtich ◽  
Kathy Gonzalez ◽  
Edith Tzeng ◽  
...  

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 205
Author(s):  
Kou Tsuyama ◽  
Nobukazu Miyamoto ◽  
Atsuhiko Shindo ◽  
Kenichiro Hira ◽  
Yuji Ueno ◽  
...  

Duplication and accessory of the middle cerebral artery (MCA) constitute a rare congenital variation. MCA anomalies are found at a lesser frequency than the vascular anomalies of the other major intracranial arteries. Duplicated/accessory MCA was usually noted incidentally with subarachnoid hemorrhage, due to resulted aneurysmal formation. However, duplicated/accessory MCA-related cerebral infarction is rarer. We report two cases of cerebral infarction due to dissection at the entry of the duplicate/accessory MCA. Both cases were similar in dissected site and clinical course, without headache or injury. In 20 previously reported cases and our two cases of duplicated/accessory MCA-related infarction, mean age (55.8 ± 21.2 years) was slightly younger for cerebral infarction, and stroke etiology was mainly embolism. The main etiologies of stroke were embolism and dissection. Considering embolism etiology, proximal site of arterial diameter changing lesion was a common site for embolism, as duplicated/accessory MCA was usually smaller than normal M1 segment. In cerebral dissection cases, the dissected site was similar to our cases. Numerous mechanisms of dissection were considered, but they mainly included dysfunction of the media and endothelium or shearing stress at the entry of duplication. As the detailed mechanisms of cerebral dissection remain unknown, clinicians should include a differential diagnosis for MCA dissection.


1971 ◽  
Vol 31 (6) ◽  
pp. 948-953 ◽  
Author(s):  
J. P. Murgo ◽  
R. H. Cox ◽  
L. H. Peterson

2007 ◽  
Vol 32 (4) ◽  
pp. 670-676 ◽  
Author(s):  
Fleur Poelkens ◽  
Mark Rakobowchuk ◽  
Kirsten A. Burgomaster ◽  
Maria T.E. Hopman ◽  
Stuart M. Phillips ◽  
...  

An increase in age coincides with a decrease in arterial compliance, which is related to a higher risk for cardiovascular accidents. Evidence regarding the effects of resistance training on arterial compliance is conflicting. Currently, little information is available about the effect of resistance training on arterial compliance in elderly men. We assessed the impact of 10 weeks of unilateral arm and leg resistance training on carotid, brachial, and femoral arterial compliance in 12 healthy elderly men (mean age ± SD, 71 ± 7 y). Arterial compliance was evaluated before, after 4 weeks, and after 10 weeks of unilateral resistance training by simultaneously measuring arterial diameter and blood pressure in each artery. There were no significant differences in arterial compliance or stiffness index in any of the arteries examined after 10 weeks of training. However, after 10 weeks of resistance training, resting heart rate decreased from 76 ± 4 beats/min to 61 ± 3 beats/min (p < 0.05), plasma glucose decreased from 6.0 ± 0.9 to 5.1 ± 0.9 mmol/L (mean ± SE) (p < 0.05), and carotid artery peak blood flow increased from 1831 mL/min to 2245 mL/min (p < 0.05). There were no significant changes in resting arterial blood pressure. Unilateral resistance training for 10 weeks does not alter peripheral and central arterial compliance elderly men.


1995 ◽  
Vol 15 (2) ◽  
pp. 143-149 ◽  
Author(s):  
P. Rørdam ◽  
H. L. Olesen ◽  
J. Sindrup ◽  
N. H. Secher

Author(s):  
Cheemun Lum ◽  
Matthew J. Hogan ◽  
John Sinclair ◽  
Shane English ◽  
Howard Lesiuk ◽  
...  

AbstractPurpose: Computed tomography perfusion (CTP) has been performed to predict which patients with aneurysmal subarachnoid hemorrhage are at risk of developing delayed cerebral ischemia (DCI). Patients with severe arterial narrowing may have significant reduction in perfusion. However, many patients have less severe arterial narrowing. There is a paucity of literature evaluating perfusion changes which occur with mild to moderate narrowing. The purpose of our study was to investigate serial whole-brain CTP/computed tomography angiography in aneurysm-related subarachnoid hemorrhage (aSAH) patients with mild to moderate angiographic narrowing. Methods: We retrospectively studied 18 aSAH patients who had baseline and follow-up whole-brain CTP/computed tomography angiography. Thirty-one regions of interest/hemisphere at six levels were grouped by vascular territory. Arterial diameters were measured at the circle of Willis. The correlation between arterial diameter and change in CTP values, change in CTP in with and without DCI, and response to intra-arterial vasodilator therapy in DCI patients was evaluated. Results: There was correlation among the overall average cerebral blood flow (CBF; R=0.49, p<0.04), mean transit time (R=–0.48, p=0.04), and angiographic narrowing. In individual arterial territories, there was correlation between changes in CBF and arterial diameter in the middle cerebral artery (R=0.53, p=0.03), posterior cerebral artery (R=0.5, p=0.03), and anterior cerebral artery (R=0.54, p=0.02) territories. Prolonged mean transit time was correlated with arterial diameter narrowing in the middle cerebral artery territory (R=0.52, p=0.03). Patients with DCI tended to have serial worsening of CBF compared with those without DCI (p=0.055). Conclusions: Our preliminary study demonstrates there is a correlation between mild to moderate angiographic narrowing and serial changes in perfusion in patients with aSAH. Patients developing DCI tended to have progressively worsening CBF compared with those not developing DCI.


1998 ◽  
Vol 76 (4) ◽  
pp. 418-427 ◽  
Author(s):  
J K Shoemaker ◽  
M E Tschakovsky ◽  
R L Hughson

The hypothesis that the rapid increases in blood flow at the exercise onsetare exclusively due to the mechanical effects of the muscle pump was tested in six volunteersduring dynamic handgrip exercise. While supine, each subject completed a series of eightdifferent exercise tests in which brachial artery blood pressure (BP) was altered by25–30 mmHg (1 mmHg = 133.3 Pa) by positioning the arm above or below the heart.Two different weights, corresponding to 4.9 and 9.7% of maximal voluntary isometriccontraction, were raised and lowered at two different contraction rate schedules (1s:1s and 2s:2swork–rest) each with a 50% duty cycle. Beat-by-beat measures of mean blood velocity (MBV)(pulsed Doppler) were obtained at rest and for 5 min following step increases in work ratewith emphasis on the first 24 s. MBV was increased 50–100% above rest following the firstcontraction in both arm positions (p < 0.05). The increase in MBV from rest was greaterin the below position compared with above, and this effect was observed following the first andsubsequent contractions (p < 0.05). However, the positional effect on the increase inMBV could not be explained entirely by the ~40% greater BP in this position. Also, the greaterworkload resulted in greater increases in MBV as early as the first contraction, compared withthe light workload (p < 0.05) despite similar reductions in forearm volume followingsingle contractions. MBV was greater with faster contraction rate tests by 8 s of exercise. Itwas concluded that microvascular vasodilation must act in concert with a reduction in venouspressure to increase forearm blood flow within the initial 2–4 s of exercise.Key words: Doppler, mean blood velocity, arterial diameter,handgrip exercise, perfusion pressure.


2009 ◽  
Vol 24 (1) ◽  
pp. 43-47 ◽  
Author(s):  
Luís Augusto da Silveira ◽  
Fernando Braga Cassiano Silveira ◽  
Valéria Paula Sassoli Fazan

PURPOSE: Despite the fact that anatomical variations of the celiac trunk are well explored in the literature, information on these vessels diameters is scanty. The aims of the present study were to describe the arterial diameters of the celiac trunk and its main branches, and to investigate if these diameters are altered in those cases presenting anatomical variations of these vessels. METHODS: Twenty-one formalin fixed adult male cadavers were appropriately dissected for the celiac trunk identification and arterial diameter measurements. Arteries measured included the celiac trunk and its main branches (splenic artery, left gastric artery and common hepatic artery), as the proper hepatic artery, right gastric artery, the left and right hepatic arteries and the gastroduodenal artery. RESULTS: From the 21 cadavers, 6 presented anatomical variations of, at least, one of the above mentioned branches. The average arterial diameter comparisons between groups (normal and variable) clearly showed smaller diameters for variable vessels, but with no significant difference. CONCLUSION: Our data indicates the possibility of a diameter reduction of the celiac trunk main branches in the presence of anatomical variations. This should be taken into account on the selection for the liver transplantation donors.


2018 ◽  
Vol 19 (9) ◽  
pp. 2489 ◽  
Author(s):  
Lin Zhang ◽  
Christian Aalkjaer ◽  
Vladimir Matchkov

Inhibition of the Na,K-ATPase by ouabain potentiates vascular tone and agonist-induced contraction. These effects of ouabain varies between different reports. In this study, we assessed whether the pro-contractile effect of ouabain changes with arterial diameter and the molecular mechanism behind it. Rat mesenteric small arteries of different diameters (150–350 µm) were studied for noradrenaline-induced changes of isometric force and intracellular Ca2+ in smooth muscle cells. These functional changes were correlated to total Src kinase and Src phosphorylation assessed immunohistochemically. High-affinity ouabain-binding sites were semi-quantified with fluorescent ouabain. We found that potentiation of noradrenaline-sensitivity by ouabain correlates positively with an increase in arterial diameter. This was not due to differences in intracellular Ca2+ responses but due to sensitization of smooth muscle cell contractile machinery to Ca2+. This was associated with ouabain-induced Src activation, which increases with increasing arterial diameter. Total Src expression was similar in arteries of different diameters but the density of high-affinity ouabain binding sites increased with increasing arterial diameters. We suggested that ouabain binding induces more Src kinase activity in mesenteric small arteries with larger diameter leading to enhanced sensitization of the contractile machinery to Ca2+.


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