No abstract

Immunocytochemistry using peroxidase antiperoxidase (PAP) techniques showed insulin-like immunoreactivity in the human retina, and in the mouse retina and optic nerve. The immunoreaction product was seen in the inner nuclear, ganglion cell, outer and inner plexiform layers of the retinas, and in glial cell bodies of the optic nerve. A similar staining pattern using antiserum to S-100 protein, a marker for glial elements, was also seen in these tissues. This demonstrates that insulin or insulin-like immunoreactivity appears to be limited to glial cells of the retina and optic nerve. Our study suggests that the presence of insulin or a similar peptide in retina and optic nerve may be important for their normal function and metabolism.

No abstract

The transverse nasal line has long been neglected and frequently overlooked. This narrow pink or hyperpigmented line or groove extends transversely between the upper two-thirds and the lower third of the nose. It is often hereditary and may be the locus of comedones and milia. Eighteen examples are reported by us, along with a possible embryological interpretation.

An immunohistochemical procedure was used to detect cells which appear to bind insulin in the mouse brain. Strong fluorescence was observed in the cell bodies and processes of tanycytes lining the third ventricle and in the choroid plexi. These findings suggest that insulin enters the central nervous system, and indicate a route for its possible transport. This adds credence to earlier observations that the hypothalamic ependymal cells and processes form a highly organized and functional system, with different cells selectively absorbing (or sensing) particular substances from the systemic and ventricular circulations and transporting them (or information about them) to specific neuron receptors in the hypothalamus.