The contribution of the left and right sympathetic trunk to control of the diameter of the femoral artery and the consecutive resistant bed.
Laterality of sympathetic control of the diameter of the femoral artery (using an inductive transformer) and the blood flow in its consecutive bed (using a Stattham flowmeter) was studied at the postganglionic level. The fibres leaving LG3, LG4 and LG5 were stimulated. Stimulation of the left sympathetic trunk (ST) evoked 88.33 +/- 0.98% of maximum sympathetic constriction of the ipsilateral and 15.0 +/- 1.1% of the contralateral femoral artery (P less than 0.001). Stimulation of the right ST evoked 86.38 +/- 0.90% of maximum constriction of the ipsilateral and 11.95 +/- 0.99% of the contralateral femoral artery (P less than 0..001). Vasomotor fibres contained in the femoral nerve exert only 23.5 +/- 3.3% (P less than 0.01), while fibres from other sources (probably including the aortic plexus) were responsible for 74.1 +/- 5.2% (P less than 0.001) of maximum constriction. The blood flow in the resistant bed consecutive to the left and right femoral artery is controlled solely by postganglionic fibres of the ipsilateral lumbar ganglia. The results indicate the variability of lateralization of the sympathetic control of the individual segments of the vascular tree.
D000818:Animals; D001794:Blood Pressure; D004285:Dogs; D004558:Electric Stimulation; D005260:Female; D005263:Femoral Artery / Q000294:innervation* / Q000502:physiology; D006614:Hindlimb / Q000098:blood supply*; D008297:Male; D012039:Regional Blood Flow; D013564:Sympathetic Nervous System / Q000502:physiology*; D014655:Vascular Resistance; D014661:Vasoconstriction