Regional cerebral blood flow in the frontal, parietal and occipital cortices increases independently of systemic arterial pressure during slow walking in conscious XXXX .

@entity4033 @entity6959 @entity3897 @entity35 @entity9966
Regional cerebral blood flow (rCBF) in the frontal, parietal and occipital cortices was measured using laser Doppler flowmetry during walking in conscious @entity35 at moderate speed on a treadmill (4 cm/s) for a 30 s period. During walking rCBF increased in all these three cortices. The rCBF in the parietal cortex started to increase within a few seconds after the start of walking, and continued to increase 42 +/- 16% (mean +/- S.D.) until the end of walking. Within 90 s after walking had ceased, the increased rCBF returned to pre-walking basal levels. The rCBF responses in the frontal and occipital cortices were identical to that in the parietal cortex. Mean arterial pressure (MAP) in a caudal artery of the tail during walking was increased by about 10%. Injection of @entity3897 (5 mg/kg, i.p.), a muscarinic cholinergic receptor antagonist that permeates the blood brain barrier (BBB), reduced the walking-induced increase in cortical rCBF, as determined by measurement of parietal rCBF, from 42 +/- 12% to 28 +/- 15%. However, injection of @entity9966 (5 mg/kg, i.p.), a muscarinic cholinergic receptor antagonist that does not permeate the BBB, did not affect the response of rCBF. Neither drug affected the walking-induced response of MAP. Injection of @entity6959 (20 mg/kg, s.c.), a nicotinic cholinergic receptor antagonist that permeates the BBB, reduced the walking-induced increase in cortical rCBF from 47 +/- 12% to 30 +/- 12%. Injection of @entity4033 (20 mg/kg, s.c.), a nicotinic cholinergic receptor antagonist that does not permeate the BBB, did not affect the responses of rCBF.(ABSTRACT TRUNCATED AT 250 WORDS)
