The role of α1- and α2-adrenoceptor subtypes in the vasopressor responses induced by dihydroergotamine in ritanserin-pretreated pithed rats

Table 2 Values of DBP and HR before and 10 min after administration of compounds

Treatment	Doses (μg/kg)	Diastolic blood pressure (DBP) (mm Hg)		Heart rate (HR) (beats/min)
Treatment	Doses (μg/kg)	Before	After	Before	After
20% (v/v) propylen glycol	1^a	55 ± 11	55 ± 12	200 ± 1	200 ± 1
Dihydroergotamine	3100	^b	^b	253 ± 45	285 ± 38
Saline^c	1^a	44 ± 5	44 ± 5	232 ± 11	232 ± 11
Prazosin^c	30	42 ± 3	42 ± 3	234 ± 8	232 ± 9
Rauwolscine^c	300	48 ± 3	51 ± 3	235 ± 11	244 ± 8
Prazosin+rauwolscine^c	30 + 300	38 ± 3	41 ± 5	252 ± 10	234 ± 8
1% (w/v) ascorbic acid	1^a	57 ± 3	60 ± 3	220 ± 12	220 ± 12
Ritanserin	100	70 ± 8	70 ± 8	193 ± 13	193 ± 13
Saline	1^a	68 ± 10	65 ± 9	201 ± 26	203 ± 27
Prazosin	10 30	74 ± 11 61 ± 5	75 ± 10 61 ± 6	243 ± 8 183 ± 31	245 ± 17 183 ± 31
Rauwolscine	100 300	63 ± 5 51 ± 3	60 ± 5 47 ± 4	213 ± 7 238 ± 13	214 ± 8 240 ± 14
Prazosin + rauwolscine	30 + 300	51 ± 4	45 ± 5	218 ± 9	224 ± 14
5-methylurapidil	30 100	50 ± 7 54 ± 9	51 ± 6 52 ± 8	228 ± 15 232 ± 14	224 ± 12 236 ± 16
L-765,314	30 100	68 ± 8 64 ± 8	65 ± 8 63 ± 10	238 ± 20 226 ± 11	240 ± 16 226 ± 11
BMY 7378	30 100	68 ± 9 63 ± 3	66 ± 10 60 ± 3	240 ± 12 256 ± 12	238 ± 12 251 ± 13
BRL44408	100 300	65 ± 4 52 ± 8	65 ± 4 53 ± 9	232 ± 22 228 ± 13	228 ± 20 225 ± 15
Imiloxan	300 1000 3000	70 ± 10 69 ± 10 68 ± 6	69 ± 9 66 ± 11 66 ± 7	246 ± 9 247 ± 9 268 ± 16	248 ± 9 252 ± 7 271 ± 16
JP-1302	300 1000	58 ± 3 63 ± 7	58 ± 3 62 ± 10	247 ± 14 212 ± 10	278 ± 13 212 ± 10

Values are presented as means ± SEM
^a1 ml/kg
^bThese values were determined before and after 1, 3.1, 10, 31, 100, 310, 1000 and 3100 μg/kg DHE, and are shown in Figs. 2, 3, 4, 5, and 6
^cThese values were obtained from control rats (non-treated with ritanserin)

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