Some Early Studies on Tissues

Coates et al. (1953) have examined the gray and white matter of rat hypothalamus with an infrared microscope and observed additional bands, which may have been the result of using a spectrometer with higher resolution than in previous studies. White matter displayed a band at 1300 cm as an inflection point, while gray matter showed one at 1163cm  

Schwarz (1960) has discussed infrared absorption analysis of tissue constituents, particularly tissue lipids. He has given a method for examining tissue sections, and has discussed the chromatography of extracted phospholipids, sphingolipids, and fatty acids and neutral lipids. 

Wegmann (1956) has studied the histochemistry of lyophilized human and freshly dehydrated rat adrenal gland cortex sections by using a microscopic attachment to an infrared spectrophotometer and compared the spectra of these glands with that of a cholesterol fraction of a lipid extract of the human adrenal. The bands obtained on the adrenal glands corresponded for the most part to steroid substances, probably steroid hormones, and to unsaturated lipid compounds. 

Wegmann et al. (1956) have published infrared spectra of rat liver microsomes and of a mixture of microsomes and mitochondria. The characteristic property of 

It is of note that erythrocytes of each vertebrate group studied, composed of complex systems of many compounds, display specific infrared absorption curves. While it is well known that the infrared spectrum of a single organic compound is one of its most characteristic physical properties, it is rather unusual to think in terms of a specific infrared spectrum of the many biochemical compounds in a living erythrocyte, but such was the case. 

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