Time course of antinociceptive and hypothermic responses to NT in rats treated i.p. with saline, antisense PNA to the NTR (AS-NTR1), or mismatch AS-NTR1 PNA. Animals received saline or PNA treatment as described in the legend to Fig. 2. Testing was every 24 hr for 3 days. Untreated control animals tested with NT alone were used to calculate the mean baseline response, which was set to 100. Data are reported as a percentage of the baseline response ± SEM as determined 30 min after drug delivery. Animals given saline (●, n = 4), AS-NTR1 PNA (▴, n = 4), or mismatch AS-NTR1 PNA (■, n = 4) were microinjected with NT (18 nmol) into the PAG and were tested for length of time on the hot plate (%MPE score) (A) and for body temperature lowering (B).