SUMMARY Cerebral glucose metabolic rate (CMRGlu), measured by positron emission tomography, was bilaterally and symmetrically reduced in two patients with autosomal dominant Alzheimer's disease. Supramarginal gyri and temporal lobes were most severely affected. An isolated reduction of CMRGlu in the left supramarginal gyrus was observed in one asymptomatic at-risk subject.

SUMMARY Young female rats were given a daily injection of 1 mg. thyroxine/kg. body weight for 7 days. They were killed on the eighth day and the small intestine used for a study of the movement of radioactive calcium and inorganic phosphate. The everted sac technique was used. The results indicate that the passive movement of phosphate was depressed. Both the passive and active transport of calcium were also depressed. It is suggested that the transport of calcium and the transport of phosphate, whether active or passive, are related and that thyroxine affects a single site located perhaps at the basement membrane of the mucosa.

A review of the current state of knowledge and speculation on fluid absorption by the gastro-intestinal tract of vertebrates and more specifically the role of hormones in fluid movement has been made. The effect of hormones on water transport, active sodium transport and the electrical characteristics of poikilotherm vertebrate, bird and mammal intestine, both in vivo and in vitro are considered. Special reference is made to the effect of aldosterone on the absorption of fluid. Data indicate that while aldosterone has an effect on other tissues such as amphibian bladder, it appears to have only a slight effect on the jejunum and only on that component of the transport phenomena associated with the transfer of sodium.

Using a new technique for determining transmucosal electrical potential difference (p.d.) and short-circuit current (Isc.) in the rat small intestine in vivo it would appear that aldosterone had no direct effect on these parameters of intestinal activity. However, adrenalectomy decreased the Isc. while after adrenalectomy aldosterone and cortisol (hydrocortisone) restored the lowered independent and probably also the lowered dependent (hexose) Isc.