Answer:
1. Inhibiting IP3 channels, leading to decreased Ca2 in the sarcoplasm and reduced contraction.
2. Increasing the relative activity of MLCP, leading to a decrease in tension.
3. Activating K channels, increasing K leaking out of the cell which hyperpolarizes it and decreases the likelihood of Ca2 entry.
Explanation
In smooth muscle, cyclic AMP (cAMP) mediates relaxation because cAMP inhibits a specific kinase required for myosin light chain protein (MLCP) phosphorylation, thereby triggering contraction in the smooth muscles. It has been shown that cAMP inhibits 1,4,5-trisphosphate (IP3)-dependent calcium ions (Ca 2+) release by activation of the cGMP-dependent protein kinase (PKG). PKG proteins act to modulate Ca2+ oscillations by stimulating sarcoplasmic Ca2+-ATPase membrane proteins, increasing Ca2+ in the sarcoplasmic reticulum stores and Ca2+ efflux from the cells, and activate voltage-gated potassium (K) channels, thereby leading to membrane hyperpolarization and reducing Ca2+ entry through Ca2+ channels.
It's metophase you are looking for :)
If you used a full active virus, that defeats the point of a vaccine. You will trigger your immune response, but since you would just be injecting the virus, it will make you sick, and your body will be less effective at fighting the pathogens.
Viruses in vaccines are weakened, so they essentially will not "fight" back. They most importantly just contains the antigen markers so the body can trigger the immune response, quickly eradicate the pathogen, and build up the memory cells to that virus.
Injecting a virus that is not weak will just be the same thing as if you got the virus, you will likely get sick.