A histochemical and biochemical investigation of -glucuronidase activity in the quiescent and secreting supra-orbital gland of Anas domesticus

Journal/Book: [From the Proceedings of the Physiological Society 14-15 April 1967] Journal of Physiology 191 89-90P. 1967;

Abstract: By B. BALLANTYNE and W. G. WOOD Department of Anatomy University of Leeds The avian supraorbital gland secretes sodium chloride following elevations in serum osmolarity and hence may be used in studies of factors regulating sodium transport. Other work suggests that butyrylcholinesterase (Ballantyne & Fourman 1967) and adenosine triphosphatase (Ballantyne & Wood 1967) may be concerned in this process. Since certain steroid hormones modify the activity of the gland (Bellamy & Phillips 1966) we have measured -glucuronidase activity in non-secreting and active glands. Twenty-four ducks were used; eight served as controls eight were given 1 g NaCl/kg body weight 1 hr before death the remainder were given 1 g NaCI/kg three times daily for 4 days. Secretions from the glands of birds given salt were collected for sodium estimations. Blood was collected before salt-loading and at death from all birds for estimation of serum sodium. Animals were killed by decapitation the supra-orbital glands removed weighed and divided into two portions. One Portion was used for the quantitative estimation of -glucuronidase by measuring the rate of liberation of phenolphthalein from phenolphthalein-mono--glucuronide at pH 45 at 37° C; free phenolphthalein was measured spectrophotometrically at 552 m at pH 105. The other portion was used for histochemical localization of the enzyme by incubating 20 thick sections in a solution containing 6-bromo-2-naphthyl--D-glucuronide as the substrate; sites of activity were revealed by coupling free naphthol with Fast Blue B (Seligman Tsou Rutenberg &. Cohen 1954). The quantitative results are shown in Table 1. ... schö

Zurück | Weiter