Table 5. Changes in heart rate during 90 minutes after intraperitoneal administration of the studied compounds.

A	time	0	5	10	15	20	30	40	50	60	70	80	90
	mean	281.5	299.8	280.2	261.8	254.2	267.5	260.5	254.7	262.0	286.5	269.2	267.2
	SEM	26.49	29.22	37.20	35.95	41.40	31.92	37.21	36.91	27.53	30.62	24.6	24.27
B	time	0	5	10	15	20	30	40	50	60	70	80	90
	mean	324.0	312.7	284.0	268.8	259.3	255.0	251.5	256.5	251.0	256.5	261.5	246.0
	SEM	12.48	15.07	8.97	7.21	6.58	8.20	13.71	18.62	22.35	18.50	21.06	18.72
						*	*	*	*	*	*	*	*
C	time	0	5	10	15	20	30	40	50	60	70	80	90
	mean	275.8	270.3	259.3	247.3	238.0	226.0	215.8	209.0	201.8	194.8	194.8	191.5
	SEM	23.12	7.48	6.70	6.85	6.31	6.06	6.84	6.40	7.17	6.80	6.80	6.91
							**	***	***	***	***	***	***
D	time	0	5	10	15	20	30	40	50	60	70	80	90
	mean	354.0	286.0	227.8	267.0	264.2	249.0	249.2	236.5	221.3	233.3	230.8	231.8
	SEM	8.63	17.40	11.95	11.18	13.88	19.44	18.39	22.67	28.29	23.97	24.29	26.38
			*	*	**	**	**	***	***	***	***	***	***

A Yohimbine 2 mg/kg b.w.; B Yohimbine 5 mg/kg b.w.; C Guanfacine 0.5 mg/kg b.w.; D Guanfacine 2 mg/kg b.w.; Signifcant vs. 0 time

*P<0.05;

**P<0.01;

***P<0.001, ONE-WAY ANOVA