theres no beta 2 receptors in blood vessels. What im saying about clenbuterol is that its selective of beta 2 but it does effect other adrenergic receptors to a lesser degree, where as adrenaline affects all the recptors to a similar degree, alot of asthma drugs supposedly affect beta2 but do have a carry over effect to other receptors, what im saying is that clenbuterol isnt a pure beta 2 agonist. if clenbuterol only caused peripheral vasoconstriction and not cerebral vasoconstriction, its still going to increase blood pressure.
Adrenaline affects all the adrenergic receptors, firstly it causes vasoconstriction through the alpha receptors which increases blood pressure, increase heart rate and strength of contraction of the heart through beta1 receptors and causes smooth muscle relaxation of the airways and uterus through beta 2. In your original post u said that beta 2 stimulation causes vasodilation, which i take u mean blood vessels dilate, which it doesnt, but it does cause the airways to relax and dilate.
Yes your right in that beta 2 are not suppose to have any effect on blood vessels but in some people it does(through stimulating alpha receptors), which increases their blood pressure, as well as an increase in heart rate can also do through beta 1 stimulation. Its common for cfsers to have low blood pressure and drugs that can increase heart rate or blood pressure can have a positive effect. but someone who has high blood pressure and then takes clenbuterol could be prone to having a stroke