Protriptylin ( Vivactil 1  ) Chemical Name: Protriptyline HCIBrand Name: Vivactil Manufacturer: Merck and CompanyDescription: Anti-depressant of unknown mechanism. Indication and Use: Vivactil is indicated for the treatment of depression in patients who are under close medical supervision.
The optic nerve (also known as cranial nerve II) is a continuation of the axons of the ganglion cells in the retina. There are approximately 1.1 million nerve cells in each optic nerve. The optic nerve, which acts like a cable connecting the eye with the brain, actually is more like brain tissue than it is nerve tissue. visual pathway
The retina converts the image formed by the light rays into nerve impulses. The optic nerve, composed of the axons of the , then transmits these impulses from the eye to the first visual relay in the brain. The axons of the collect in a bundle at the and emerge from the back of of the eye to form the optic nerve. The optic nerve is the pathway that carries the nerve impulses from each eye to the various structures in the brain that analyze these visual signals.