TABLE II.

Percentage change in cardiovascular variables in response to A Ch and to A Ch after antagonist injections

Percent change is based on control values taken immediately prior to injections.

	n	Control		ACh		Antagonists		ACh
		MAP	HR	MAP	HR	MAP	HR	MAP	HR
Atropine
Pons	4	100	100	78.0 ± 5.9	117.5 + 8.8	101.3 ±2.2	96.8 ± 1.7	90.8 ±2.2**	106.3 ± 4.3
Medulla
local (14 mM)	8	100	100	68.4 ± 13.1	111.8 ± 12.8	101.4 ±2.7	99.1 ±2.0	85.5 + 10.2*	104.1 ±5.2
IV (1 mg/kg)	3	100	100	74.3 + 6.5	114.0 ±5.3	101.3 ±3.1	98.7 ±1.5	92.0 ± 4.4*	102.3 ± 6.4
HMT (12.4 mM)
Pons	4	100	100	83.0 ±5.4	112.0 ± 10.2	101.0 ±2’.2	98.0 ±0.8	83.8 + 6.9	110.8 ±9.4
Medulla	3	100	100	61.3 ±3.2	111.0 ±12.1	100.0 ±4.6	101.0 ±3.6	64.0 ±3.0	109.3 ±10.1

^*P < 0.05,

^**P < 0.01, comparing cardiovascular changes induced by ACh injection alone with that produced by ACh injection after antagonists.