Occurrence of Free Alpha Subunit of the Thyroid Stimulating Hormone Family in Pituitaries of Water Buffaloes (Bubalus bubalis)

Abstract

Presence of free alpha subunit has been noticed in a side fraction obtained during the processing of buffalo pituitary glands for thyrotropin and gonadotropins using standard isolation and fractionation procedures. In addition to the gel chromatographic data (Ve/Vo), when the material was analyzed with different antisera, it clearly reacted with alpha subunit directed antibodies. The NaCI precipitation method of Sairam for the separation of the free subunits from each other was applied to the material. The yield of the alpha subunit by the NaCI precipitation method with respect to the immunogenicity and the content was higher than what was obtained by the counter current distribution.

The sugar content of the free alpha subunit was less (70 μg/mg) compared to the sugar content of the alpha subunit isolated by the dissociation from the intact hormone (204 μg/mg). Most of the free alpha subunit eluted as the unbound fraction from a Concanavalin A sepharose column thus supporting the idea that there was an alteration in carbohydrate structure in these naturally occurring free subunits.