Reaction of Pial Arteries and Veins to Sympathetic Stimulation in the Cat

The diameters of pial arteries and veins were continuously monitored by a multichannel videoangiometer through a closed cranial window in 13 cats. Seventy-two arterial portions (diameter 30-283 (im) and 103 venous segments (diameter 32-486 pm) were studied under resting conditions and during stimulation of the cervical sympathetic chain. Arteries with a diameter of <. 150 pm constricted 7.3 ± 0.8%; those > 150 fim 13.1 ± 1.4% (P <, 0.0005 for both groups). Veins constricted significantly more than arteries of corresponding size (P < 0.005). Veins <. 150 urn constricted 11.5 ± 0.9% and those S; 150 fun constricted 19.9 ± 1.9% (P < 0.0005 for both groups compared to resting levels). Since the venous compartment contains about 70% of the regional blood volume the tone of the veins is of importance for intracranial pressure. Further studies on the role of sympathetic nervous activity in the regulation of cerebral venous tone under physiological and pathological conditions seem essential. Stroke, Vol 12, No 4,1981

[1]  W. Kuschinsky,et al.  Alpha‐Receptor Stimulation by Endogenous and Exogenous Norepinephrine and Blockade by Phentolamine in Pial Arteries of Cats , 1975, Circulation research.

[2]  L M Auer,et al.  Pial venous constriction during cervical sympathetic stimulation in the cat. , 1980, Acta physiologica Scandinavica.

[3]  Pathogenesis of hypertensive encephalopathy. , 1973, Lancet.

[4]  H. Wolff,et al.  CEREBRAL CIRCULATION: III. THE VASOMOTOR CONTROL OF CEREBRAL VESSELS , 1928 .

[5]  M. Marcus,et al.  Response to ‘Do Vasomotor Nerves Significantly Regulate Cerebral Blood Flow?’ , 1978, Circulation research.

[6]  M. Purves.  CONTROVERSIES IN CARDIOVASCULAR RESEARCH* Do Vasomotor Nerves Significantly Regulate Cerebral Blood Flow?f , 1978 .

[7]  L. Edvinsson,et al.  Evidence of vasoconstrictor sympathetic nerves in brain vessels of mice , 1973, Neurology.

[8]  J. Patterson,et al.  Determinants of Response of Pial Arteries to Norepinephrine and Sympathetic Nerve Stimulation , 1975, Stroke.

[9]  J. Patterson,et al.  Comparison of the open skull and cranial window preparations in the study of the cerebral microcirculation. , 1978, Microvascular research.

[10]  L. Edvinsson,et al.  Autonomic Nervous Control of Cerebrospinal Fluid Production and Intracranial Pressure , 1983 .

[11]  E. Mackenzie,et al.  Amine mechanisms in the cerebral circulation. , 1976, Pharmacological reviews.

[12]  C. Owman,et al.  Adrenergic innervation of pial arteries related to the circle of Willis in the cat. , 1967, Brain research.

[13]  Ludwig Michael Auer,et al.  The Pathogenesis of Hypertensive Encephalopathy , 1978, Acta Neurochirurgica.