You can BLOCK the DECREASE in theart rate following parasymp

You can BLOCK the DECREASE in theart rate following parasympathetic nervous system activation with an intravenous injection of

Solution

Answer: d. either A or B

Reason:

It is possible to inhibit the decrease in heart rate following parasympathetic nervous system activation with an intravenous injection of either a nicotinic acetylcholine receptor antagonist because these antagonists can interfere with postsynaptic fibres of neurons innervated with heart via baroreflex finally causes change in blood pressure and increase in heart rate. The muscarinic acetylcholine receptor antagonists, such as atropine can increase heart rate by blocking M2Ach binding receptors on heart muscle finally cause tachycardia or higher heart rate