carotid chemoreceptor excitation , produced by hypoxia ( end-tidal po2 approximately equal to 50 torr ) or by sodium cyanide injection ( 50-100 micrograms , i.v . ) , elicited 3 types of responses : ( 1 ) the psn discharged during the silent period of pn activity , although the psn peak activity was still coupled to the pn peak activity , ( 2 ) psn discharged only during pn activity , and ( 3 ) during the absence of pn discharge induced by hyperventilation hypocapnia , cyanide injection stimulated the psn without pn activity .
C0037498
sodium cyanide
C0010505
cyanide