How to get lots of comments on instagram dramamine Радужка contains the pigmentary cages defining colour of an eye and an aperture - a pupil (pupilla), playing a role of a diaphragm for rays of light getting into an eye. In радужке there are two muscles: кольцевидный сфинктер, a narrowing pupil (muse, sphincter pupillae) and an expanding pupil (muse, dilatator pupillae), the first of them иннервируется глазодвигательным a nerve, the second - sympathetic. Muscles радужки regulate diameter of a pupil (зрачковый a reflex) depending on light exposure. So, at very bright light diameter of a pupil minimum (1,8 mm), at average light exposure - 2,4 mm, and in the dark - maximum (7,5 mm). Off label use of exelon patch