Final answer:
Isoproterenol is an IV induction medication with cardio-stimulating effects due to its mimicry of epinephrine and norepinephrine, enhancing heart rate and the force of cardiac contractions by increasing intracellular calcium levels.
Step-by-step explanation:
The IV induction medication known for having cardio-stimulating effects is isoproterenol. Isoproterenol, like dopamine, mimics the action of natural catecholamines such as epinephrine and norepinephrine and binds to beta receptors on cardiac muscle to increase metabolic rate and force of contraction. This effect results in an increase of heart rate (positive chronotropy) and the strength of the heart's contraction (positive inotropy).
It is important to note that these synthetic drugs increase the influx of calcium ions, leading to higher concentrations of intracellular calcium, which also contributes to the increased force of contractions. In contrast, parasympathetic stimulation, which does the opposite, results in decreased heart rate and strength of contraction, as seen with the action of acetylcholine released from the vagus nerve.
On the other hand, drugs like beta-blockers work to counter opposite effects by blocking beta receptors, thus reducing heart rate and the force of contractions, benefitting individuals with certain cardiovascular conditions. This distinction highlights the significance of sympathetic stimulation in mediating cardio-stimulating effects through medications like isoproterenol.