Identification and Distribution of m- and p-Hydroxyphenylacetic Acids in the Brain of the Rat

The m and p isomers of hydroxyphenylacetic acid have been identified and quantitated in whole rat brain and in several regions using a capillary column high resolution gas chromatography–mass spectrometry procedure. Their concentrations were: for m-hydroxyphenylacetic acid (mean ± S.E., number of determinations in parentheses)—whole brain, 2.3 ± 0.3 ng/g (7); hypothalamus, 1.2 ± 0.3 ng/g (5); caudate nucleus, 5.5 ± 0.6 ng/g (5); brain stem, 1.8 ± 0.1 ngig (5); cerebellum, 1.2 ± 0.1 ng/g (5) and the “rest,” 1.7 ± 0.1 ng/g (5); and for p-hydroxyphenylacetic acid–whole brain, 10.6 ± 0.7 ng/g (7); hypothalamus, 4.5 ± 0.1 ng/g (4); caudate nucleus, 28.3 ±1.6 ng/g (5); brain stem, 8.6 ± 0.6 ng/g (5); cerebellum, 8.1 ± 0.4 ng/g (9, and the “rest,” 5.3 ± 0.5 ng/g (5). This heterogeneous distribution parallels closely that exhibited by their respective precursor amines, m- and p-tyramine.     

Dinoflagellate sterols IV: Isolation and structure of 4α,23ξ,24ξ-trimethylcholestanol from the dinoflagellate Glenodiniumhallii

The dinoflagellate $\text{Glenodinium}$$\text{hallii}$ was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5-en-3β-ol, (24ξ)-24-methylcholest-5-en-3β-ol, stigmasta-5,22-dien-3β-ol, (22E,24R)-4α,23,24-trimethyl-5α-cholest-22-en-3β-ol, and 4α,23ξ,24ξ-trimethyl-5α-cholestan-3β-ol.     

Milk prolactin is biologically active

Fat-free milk from cow and goat was chromatographed on Sephadex G-100 and the prolactin (PRL) activity of the fractions determined by radioimmunoassay (RIA). A single prolactin component was observed in 3 cow and 3 goat milk samples with a Vf/Vt ratio of approximately 0.5. Fractions in which PRL was detected by RIA and fractions on either side of the PRL peak were combined, dialyzed and freeze dried. The fractions were assayed for biological activity using the pseudopregnant rabbit mammary gland in organ culture; the degree of secretory response was evaluated histologically. Milk prolactin was biologically active. In the RIA cow milk PRL and one of 2 samples of goat milk PRL gave dose response curves parallel with the bovine PRL standard. In the bioassay the dose response curves for cow milk PRL and ovine PRL were parallel while goat milk PRL was parallel when the results were compared on a weight basis but not on the basis of prolactin content of the preparations assayed by RIA.     

Catecholamine metabolites in human plasma as indices of brain function: Effects of debrisoquin

Metabolites of catecholamine neurotransmitters in plasma are, potentially, an easily available indicator of brain function in man. The peripheral contribution to these metabolites was lowered by debrisoquin sulfate, a monoamine oxidase inhibitor that does not enter the brain. In the monkey, it had been shown that debrisoquin decreased peripheral production of the dopamine metabolite, homovanillic acid (HVA), without changing production by brain; production of the norepinephrine metabolite, 3-methoxy-4-hydroxyphenethyleneglycol (MHPG) was decreased peripherally and in brain. Low-dose debrisoquin administration in man eliminated about 80% of the peripheral contribution to HVA and MHPG in plasma, resulting in a situation in which at least 75% of these metabolites in plasma were from the brain. Under these conditions, HVA and MHPG in plasma had a significant correlation. It could also be estimated that production of MHPG by brain was reduced 55%. Debrisoquin potentially provides a method for studying brain catecholamines through their metabolites in plasma and for treating conditions of brain noradrenergic excess.     

Skin temperature biofeedback and migraine headaches

To assess the relative contribution of specific and nonspecific effects of skin temperature biofeedback upon migraine headache, 11 migraine patients were taught to increase the temperature of their hand. Training to decrease the skin temperature of the hand served as a control for 12 other migraine patients. An additional 11 control subjects were not trained but kept records of migraine activity. Under carefully controlled double-blind procedures, migraine patients who learned to raise finger temperatures showed statistically significant and clinically therapeutic improvement during a 6-week follow-up period. However, they were not significantly better than those trained to lower finger temperatures, those who did not meet a learning criterion, or those receiving no training. While these groups did show some significant improvement when compared to subjects who learned to decrease finger temperature, the results are most parsimoniously explained through nonspecific rather than specific factors. The necessity of using double-blind procedures in evaluating therapeutic effectiveness is again stressed.This article was presented as a Citation Award Paper at the Biofeedback Society of America meetings, San Diego, 1979. The work was supported in part by Rehabilitation Services Administration Grant No. 16-P-56810/5-17 to the University of Minnesota Medical Rehabilitation Research and Training Center and by a grant from the Division of Health Care Psychology, University of Minnesota. We would like to acknowledge the advice and support of Lee Willerman and John Belknap. We are grateful for the assistance of John Hendrickson, Dale Armin Miller, and Stephanie Waddingham in conducting the study and for the technical assistance of Robert Patterson, Steve Sheffield, P. Thain Marston, Kathy Guttormson, and Nancy Belknap.     

High-performance liquid chromatographic and gas—liquid chromatographic determination of diazepam and nordiazepam in plasma

A one-step method for extraction of diazepam, nordiazepam, and internal standard into toluene is followed by chromatographic separation and detection with either dual-wavelength high-performance liquid chromatography or electron-capture gas—liquid chromatography. Agreement between the two methods was excellent for diazepam (r = 0.99, n = 38) and good for nordiazepam (r = 0.96, n = 79) over a concentration range that included subtherapeutic, therapeutic, and toxic plasma levels.     

Evaluation of the potential of a bead mill for the release of intracellular bacterial enzymes

The suitability of bead mills for the release of intracellular bacterial enzymes has been studied using the Dyno-Mill Model KDL. The effect of cell concentration, bead size and agitation speed on the release of beta-lactamase from Enterobacter cloacae P99 was examined. Scale-up considerations included, the best operational values for these parameters were 1 g cell paste suspended in 2.5 ml buffer, 0.25 mm diameter glass beads and 15 ms ⁻¹ agitation speed. These conditions proved suitable for the release of enzymes from other Gram-negative bacteria in both batch and continuous processes.     

Evaluation of immobilized cytochrome P-448 from Saccharomyces cerevisiae using permeabilized whole cell, microsomal fraction and highly purified reconstituted forms, with benzopyrene-3-monooxygenase activity

Cytochrome P-448 from Saccharomyces cerevisiae in permeabilized whole cell, microsomal fraction and in a highly purified reconstituted benzopyrene-3-monooxygenase (EC 1.14.14.1) system have been immobilized on various supports. Calcium alginate was found to be especially useful and the kinetics of hydroxylation were close to that of the free enzyme system with all three forms of enzyme, even with permeabilized whole yeast cells (V _max of 664 pmol 3-hydroxybenzo(a)pyrene produced per h per nmol cytochrome P-448 compared with 1000 for free highly purified reconstituted enzyme system). Only the highly purified reconstituted form was successfully immobilized by BrCN-activated Sepharose-4B or by acrylamide. Both of these supports stabilized the highly purified reconstituted cytochrome P-448 benzopyrene-3-monooxygenase activity in prolonged storage at 4°C. Applications for various immobilized enzymes and cells are assessed.     

The appearance of an extracellular arylsulfatase during morphogenesis of the sea urchin Strongylocentrotus purpuratus

An increase in arylsulfatase activity occurs after hatching in embryos of the sea urchin Strongylocentrotus pupuratus. The bulk of this increase can be attributed to the accumulation of an extracellular activity, since it can be removed by an embryo dissociation medium or upon protease treatment of intact embryos. Also, intact embryos can hydrolyze exogenous substrate, displaying activity equivalent to that which can be removed by the dissociation or protease treatment. The data indicate that the activity appears as a newly secreted molecule ionically coupled to a membrane site or to other components in the extracellular matrix. The majority of the activity is a single component of apparently large molecular size (analyzed on polyacrylamide gel electrophoresis), consistent with the suggestion that it may be complexed with other extracellular components. A morphogenetic role for this enzyme is suggested by the appearance of the extracellular sulfatase temporally coincident with the requirement of sulfated proteoglycans and glycoproteins for cell movement and shape changes.