Moosavi S H, Topulos G P, Hafer A, Lansing R W, Adams L, Brown R, Banzett R B
Physiology Program, Room 309, Building 1, Harvard School of Public Health, 665 Huntington Avenue, Boston, MA 02115, USA.
Respir Physiol. 2000 Aug;122(1):45-60. doi: 10.1016/s0034-5687(00)00135-3.
Breathing sensations of AIR HUNGER, WORK and EFFORT may depend on projections of central motor discharge (corollary discharge) to the forebrain. Source of motor drive (brainstem or cortex) may determine what is perceived. To test the effect of changing motor discharge at constant ventilation, we induced partial neuromuscular blockade during hypercapnic hyperpnea (31 + or - 9 L min(-1); PET(CO(2))=49 + or - 2 Torr) and during matched volitional hyperpnea (34 + or - 5 L min(-1); PET(CO(2))=41 + or - 1 Torr). Decline of vital capacity was similar between conditions (39%). Ventilation was unchanged with paralysis, indicating increased respiratory motor drive to maintain hyperpnea. Sensations were rated on a seven point ordinal scale. Median EFFORT and WORK increased 3-3.5 points with paralysis during both forms of hyperpnea (P<0.02, Wilcoxon signed rank). Median AIR HUNGER increased 2.5 points with paralysis during hypercapnic (P<0.02) but not during volitional hyperpnea. Data suggests that EFFORT and WORK arise from motor cortex activity (subjects reported engaging volitional control when paralyzed even during hypercapnia) and suggests that AIR HUNGER arises from medullary motor activity.
空气饥饿感、呼吸功和用力的呼吸感觉可能取决于中枢运动放电（伴随放电）向前脑的投射。运动驱动源（脑干或皮层）可能决定所感知到的内容。为了测试在恒定通气情况下改变运动放电的影响，我们在高碳酸血症性通气过度（31±9升/分钟；呼气末二氧化碳分压=49±2托）和匹配的自主性通气过度（34±5升/分钟；呼气末二氧化碳分压=41±1托）期间诱发了部分神经肌肉阻滞。两种情况下肺活量的下降相似（39%）。麻痹时通气量不变，表明呼吸运动驱动增加以维持通气过度。感觉采用七点序数量表进行评分。在两种通气过度形式中，麻痹时用力和呼吸功的中位数增加3 - 3.5分（P<0.02，Wilcoxon符号秩检验）。在高碳酸血症性通气过度期间，麻痹时空气饥饿感的中位数增加2.5分（P<0.02），但在自主性通气过度期间未增加。数据表明，用力和呼吸功源于运动皮层活动（受试者报告即使在高碳酸血症期间麻痹时也参与了自主控制），并表明空气饥饿感源于延髓运动活动。
