Q- Which of the following is the mechanism of action of metoprolol in treating hypertension and arrhythmias?
A- β1 -Selective adrenoreceptor agonist
B- β1 -Selective adrenoreceptor antagonist
C- Blocks Ca 2+ entry in vascular smooth muscle cells
D- Reduces production of angiotensin II
Q- Which of the following is the receptor site of action of sumatriptan?
A- Dopamine receptor
B- GABAB receptor
C- Glycine receptor
D- Serotonin 5-HT
Q- Which of the following drugs is a weak partial agonist of estrogen receptor in most tissues?