Drug for the treatment of erectile dysfunction. Is a reversible selective inhibitor of specific phosphodiesterase type 5 (PDE5) cGMP.
When sexual stimulation causes local release of nitric oxide,  inhibition of PDE5 tadalafil leads to increased levels of cGMP in the  cavernous body Buy Cialis of penis.
The result is relaxation of smooth muscles of arteries and blood flow to the tissues of the penis, causing erection.

Cialis(Tadalafil) has no effect without sexual stimulation.
In vitro studies have shown that Cialis(Tadalafil)  is a selective inhibitor of PDE5. PDE5 - an enzyme found in smooth  muscle of the corpus cavernosum, in vascular smooth muscle of internal  organs, skeletal muscle, platelets, kidney, lung, cerebellum.

The action of Cialis(Tadalafil) for PDE5 is more active than other phosphodiesterase.

Tadalafil  10 000 times more potent for PDE5 than for FDE1, FDE2, PDE4, FDE7,  which are located in the heart, brain, blood vessels, liver, leukocytes,  skeletal muscle and other organs. Buy Cialis Online is 10 000 times more active blocks PDE5 than FDE3 - an enzyme that is found in the heart and blood vessels.

This  selectivity for PDE5 compared with FDE3 is important, because FDE3 is  an enzyme participating in the reduction of the heart muscle.
Additionally,Cialis(Tadalafil)  is approximately 700 times more potent for PDE5 than for FDE6, found in the retina and is responsible Buy Cialis Online for fotoperedachu.

Cialis(Tadalafil)  is also showing the action in 9000 times more potent for PDE5, compared  with its effect on FDE8, 9 and 10 and 14 times more potent for PDE5  compared with FDE11.
Tissue distribution and physiological effects of inhibiting FDE8-FDE11 has not yet been clarified.Cialis improves erection and the possibility of successful sexual intercourse.The drug acts for 36 h.

The effect is already 16 minutes later reception of the product in the presence of sexual arousal.

Cialis(Tadalafil)  in healthy individuals does not cause significant changes in systolic  and diastolic blood pressure compared with placebo in the supine  position (mean maximum decrease of 1.6/0.8 mm Hg, respectively) and  standing (mean maximum decrease of 0.2/4.6 mm Hg, respectively .)  does not cause significant changes in heart rate.

Cialis(Tadalafil)  does not cause changes in the recognition of colors (blue / green),  because of its low affinity for FDE6. In addition, no marked effect of  tadalafil on visual acuity, electroretinogram, intraocular pressure and  pupil size.Cialis(Tadalafil) does not cause changes in testosterone Buy Cialis Online Cheap  LH and FSH in blood plasma.There were no clinically significant effect  on the characteristics of sperm in men taking tadalafil in daily doses  for 6 months in placebo-controlled studies.