Characterization and measurement of [125I]iodopindolol binding in individual rat pineal glands: existence of a 24-h rhythm in beta-adrenergic receptor density.

A simple procedure has been developed that permits measurement of beta-receptors in membrane preparations from individual rat pineal glands using [125I]iodopindolol ([125I]PIN). [125I]PIN binding to pineal membranes was stereospecific and saturable. Scatchard analysis of saturation isotherms yielded a Kd of 147.

Supersensitivity of the noradrenergic system in the spinal cord following intracisternal injection of 6-hydroxydopamine.

The intracisternal administration of 6-hydroxydopamine (6-OHDA; 100 micrograms on two consecutive days) resulted in a 90-95% depletion of norepinephrine (NE) in the spinal cord 3-60 days following administration of the drug. At 90 days following injection of 6-OHDA, the depletion was only 60% suggesting the regrowth of NE-containing fibers. Consistent with the depletion of NE, 3-60 days after the injection of 6-OHDA a 50-80% decrease in the uptake NE occurred with only a 25% decrease 90 days after administration of 6-OHDA.

Protective effect of taurine on the light-induced disruption of isolated frog rod outer segments.

Isolated frog rod outer segments (ROS) incubated in a Krebs-bicarbonate medium, and illuminated for 2 h, show a profound alteration in their structure. This is characterized by distention of discs, vesiculation, and a marked swelling. The light-induced ROS disruption requires the presence of bicarbonate and sodium chloride.

Taurine effects on 45Ca2+ transport in retinal subcellular fractions.

The effect of taurine on 45Ca2+ transport by subcellular fractions from the chick retina was examined. An inhibitory action of taurine on 45Ca2+ uptake was observed in retinal fractions incubated for 1--5 min in a Krebs--bicarbonate medium, pH 7.4.