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Postsynaptic density (PSD) fractions were isolated from the cerebral cortices of control and kindled rats and assayed for glutamate and y-aminobutyric acid-binding capacities and for the Ca2+/calmodulin-dependent protein kinase. Glutamate binding was found to be increased by =50% in the PSDs isolated from kindled rats as compared to controls; this increase was almost completely from an increase in B..;Kd decreased only slightly. Studies with inhibitors indicate that the receptors involved were of the N-methyl-D-aspartate and quisqualate types. PSDs isolated from control and kindled rats did not differ in y-aminobutyric acid or flunitrazepam binding.The in vitro autophosphorylation of the Ca2+/calmodulindependent protein kinase was depressed by 45-76% in PSDs isolated from kindled rats as compared to controls, with little change in amount of the kinase. Therefore, we infer that (i) the kindled state is associated with an increase in glutamate activation of postsynaptic sites, allowing Ca21 to enter dendritic spines, (ii) a change has occurred in activity ofthe protein kinase, which is the major cerebral cortex PSD protein, and (iii) perhaps major alterations in the PSD are a concomitant to the long-lasting nature of the kindled state.Kindling is the term coined by Goddard (1) to describe the progressive development, in response to initially subthreshold electrical stimulation of specific brain sites, of epileptic seizures that progressively spread and increase in intensity. Progression of the kindling phenomenon is characterized by increases in after-discharge duration and amplitude (2-5), a spread to secondary sites (5, 6), and decreases in threshold in distant cortical sites (2). Kindling shows remarkable temporal and spatial specificity as seen in many species from frog (7) to subhuman primates (8) and, once established, may persist without further stimulation for the life of the animal (9). After sufficient training, some animals develop spontaneous seizures (10). Strong pharmacological evidence indicates that this phenomenon is generated through stimulation of identifiable synaptic populations (11). Kindling by stimulation of the medial septal nuclei is associated with a decrease in the activity of the enzyme calmodulin kinase II in cortex and hippocampus (12, 13). However, calmodulin kinase II is a ubiquitous enzyme in brain. It is present in the presynaptic apparatus (14) where it may regulate transmitter biosynthesis by phosphorylation of 5-tyrosine and 5-tryptophan hydroxylases (15) and may regulate transmitter release via synapsin I phosphorylation (16). The enzymatic activity is also present in large quantities postsynaptically, particularly in postsynaptic densities (17), and calmodulin kinase II appears identical to the major postsynaptic density (PSD) protein (18)(19)(20). The goal of our study was to investigate whether any biochemical changes in isolated PSDs, such as neurotransmitter binding and phosphorylations, were associated with septal kindling. METHODSKindling. Male Sprague-Dawley r...

We were able to detect hemihypertrophy of a fetus in a routine prenatal ultrasound examination. The presence of hemangiomas and varicose veins in the hypertrophied left lower extremity at birth enabled us to diagnose the Klippel-Trenaunay-Weber syndrome. The possibility of a congenital arteriovenous fistula causing the constellation of findings was ruled out by a nuclear flow study and a thorough physical examination. A computerized tomographic scan revealed that the hemangiomas were superficial in the hypertrophied left lower extremity and did not interrupt the deep muscle bundles.

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A method is presented for the separation of epidermal strata by the successive elimination of either the basal or basal and spinous cells with 0.24 M NH4Cl at pH 9.5. Histologic evidence suggests that the residual epidermal strata obtained after incubation of the skin with NH4Cl are reproducible; hence, this technique circumvents loss of granular layer histidine-rich protein inherent with trypsin separation and provides an effective procedure for biochemical analysis of arginine-rich and lysine-rich proteins in the various differentiating epidermal cells.