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P H Patterson

Publications and source records attributed to P H Patterson.

At least 109 records · Page 6Linked to original sources
PubMed1989

The cholinergic neuronal differentiation factor from heart cells is identical to leukemia inhibitory factor.

A protein secreted by cultured rat heart cells can direct the choice of neurotransmitter phenotype made by cultured rat sympathetic neurons. Structural analysis and biological assays demonstrated that this protein is identical to a protein that regulates the growth and differentiation of embryonic stem cells and myeloid cells, and that stimulates bone remodeling and acute-phase protein synthesis in hepatocytes. This protein has been termed D factor, DIA, DIF, DRF, HSFIII, and LIF. Thus, this cytokine, like IL-6 and TGF beta, regulates growth and differentiation in the embryo and in the adult in many tissues, now including the nervous system.

Amino Acid Sequence↗
PubMed1989

Water consumption and fecal moisture of laying hens fed wheat middlings and corn-soybean-alfalfa meal diets.

Hens, housed on the floor and fed a diet containing 89% wheat middlings (WM) either as mash or pellets, consumed more feed and water than hens fed corn-soybean meal-alfalfa meal (CSA) diets with either .15, .50, or .75%. NaCl. Moisture content of the hens' feces was not affected by mash or pellet processing of the WM diet. Feeding the .75% NaCl-CSA diet, however, significantly increased fecal moisture beyond that observed with the other treatments. Caged layers fed the WM diet voided more feces (2.6 fold) than did caged layers fed the .50% NaCl-CSA diet, suggesting that wet litter problems observed in the floor pens of birds fed WM were the result of a greater fecal volume voided rather than a higher moisture content per unit of feces.

Animal Feed↗
PubMed1987

Differences in monoamine oxidase activity between cultured noradrenergic and cholinergic sympathetic neurons.

Two types of monoamine oxidase activity (MAO-A and MAO-B) help regulate the levels of biogenic amines such as catecholamines and serotonin. Although MAO-A has greater activity toward most catecholamines than MAO-B, no direct experiments have determined the types and levels of MAO activity that are normally expressed in noradrenergic neurons. Noradrenergic neurons from neonatal rat superior cervical ganglia were isolated and cultured under conditions that permit either continued expression of the noradrenergic phenotype or promote a transition to a predominantly cholinergic phenotype. After 14-21 days in vitro, neurons from both types of cultures were assayed for the type and amount of monoamine oxidase activity using tryptamine, a common substrate for both MAO-A and MAO-B. Neurons cultured under noradrenergic conditions expressed sevenfold greater MAO activity than neurons cultured under cholinergic conditions. Essentially all MAO activity in the noradrenergic cultures was inhibited by preincubation with 10(-8)-10(-9) M clorgyline, which indicated that this activity was primarily MAO-A. Cultures grown under cholinergic conditions exhibited 6- to 10-fold lower MAO-A activity and an 8- to 10-fold lower level of catecholamine synthesis from labeled precursors compared to neurons grown under noradrenergic conditions. These results directly demonstrate that high MAO-A activity is expressed in noradrenergic neurons in vitro. The corresponding decreases in both MAO-A specific activity and catecholamine synthesis as neurons become cholinergic in vitro suggest that the expression of the noradrenergic phenotype involves the coordinate regulation of degradative as well as synthetic enzymes involved in catecholamine metabolism.

Animals↗
PubMed1987

Characterization of an inhibitor of neuronal plasminogen activator released by heart cells.

A basic understanding of growth cone dynamics and developmental events involving growth cones requires an understanding of the function and regulation of molecules associated with and released by growth cones. Rat sympathetic neurons in culture release a urokinase-like plasminogen activator from their distal processes and/or growth cones (Pittman, 1985a). When sympathetic neurons are grown in cocultures with heart cells, however, plasminogen activator activity is not detected. The absence of plasminogen activator activity in cocultures of sympathetic neurons and heart cells appears to be due to the release of an inhibitor of plasminogen activator by heart cells. This inhibitor has a molecular weight of approximately 50 kDa in the presence of SDS and apparent molecular weights of approximately 50 and greater than 2000 kDa under native conditions. A significant fraction of the large-molecular-weight form of the inhibitor is converted to the smaller form following treatment with heparinase. Extremely stable complexes of 68 and 80 kDa are formed between the heart inhibitor and the plasminogen activator, urokinase, such that the complexes withstand boiling in SDS/mercaptoethanol. The data are consistent with the formation of an 80 kDa urokinase-inhibitor complex in the presence of heparan sulfate proteoglycan and a 68 kDa complex in the absence of heparan sulfate proteoglycan. A highly purified preparation of the heart inhibitor produces a 2- to 3-fold increase in neurite outgrowth from sympathetic neurons. These data indicate that the activity of the plasminogen activator released by sympathetic neurons can be regulated by a normal target tissue and that this regulation may result in increased neurite outgrowth from the neurons.

Animals↗
PubMed1986

A monoclonal antibody that blocks the activity of a neurite regeneration-promoting factor: studies on the binding site and its localization in vivo.

Work from several laboratories has identified a proteoglycan complex secreted by a variety of non-neuronal cells that can promote neurite regeneration when applied to the surface of culture dishes. Using a novel immunization protocol, a monoclonal antibody (INO) was produced that blocks the activity of this outgrowth-promoting factor (Matthew, W. D., and P. H. Patterson, 1983, Cold Spring Harbor Symp. Quant. Biol. 48:625-631). We have used the antibody to analyze the components of the active site and to localize the complex in vivo. INO binding is lost when the complex is dissociated; if its components are selectively reassociated, INO binds only to a complex containing two different molecular weight species. These are likely to be laminin and heparan sulfate proteoglycan, respectively. On frozen sections of adult rat tissues, INO binding is present on the surfaces of glial cells of the peripheral, but not the central, nervous system. INO also binds to the basement membrane surrounding cardiac and skeletal muscle cells, and binding to the latter greatly increases after denervation. In the adrenal gland and kidney, INO selectively reacts with areas rich in basement membranes, staining a subset of structures that are immunoreactive for both laminin and heparan sulfate proteoglycan. In general, the outgrowth-blocking antibody binds to areas known to promote axonal regeneration and is absent from areas known to lack this ability. This suggests that this complex, which is active in culture, may be the physiological substrate supporting nerve regeneration in vivo.

Animals↗
PubMed1986

Mechanical properties of the tibiotarsus of broilers and poults loaded with artificial weight and fed various dietary protein levels.

Bone strength comparisons were made on tibiotarsi of chicks and poults fed various levels of dietary protein and either loaded or not loaded with artificial weights. Stress and modulus of elasticity were evaluated for their ability to measure strength and rigidity differences in bones while accounting for various bone size. Often comparisons between birds of different ages and body weights are attempted despite various bone size and dimension. These terms identified the weaker, less rigid bones in a comparison between chicks fed a low calcium, low phosphorus diet and a control group matched for age, weight, and bone size. Stress values were not significantly different when ad libitum-fed controls and restriction-fed controls were compared even though body weights were significantly different. This suggests that bone strength comparisons can be made on bones that differ in size. Artificial weight loading of chicks or poults had no consistent effect on stress or modulus of elasticity. This would suggest that this type of exercise had no influence on bone strength. Turkey poults fed 28% dietary protein appeared to have stronger bones than those fed lower protein levels; however, when bone size and dimension are accounted for, no differences in bone strength resulted from the feeding of various protein levels. These findings suggest that stress and modulus of elasticity are better terms to use than force in making bone strength comparisons between groups of birds which may differ in body size and bone dimension.

Animals↗
PubMed1985

Protein requirements of mature working horses.

Eighteen mature horses were used to study proteins requirements of working horses. Treatments included intense exercise, medium exercise and maintenance in a 3 X 3 factorial arrangement with three levels of calculated dietary crude protein (CP; 8.5, 7.0 and 5.5%). The horses were on the various exercise-protein treatments for 60 d, then fasted 4 d to evaluate their N status after the treatment period. Exercise had no significant effect on body weight over the feeding and fasting periods. No one exercise or protein treatment expressed the classical low plasma albumin or total protein concentrations of protein-deficient or malnourished animals. Plasma urea N (PUN) concentrations reflected the amount of protein in the diet, with the horses fed the high-protein treatment having the highest PUN concentration (P less than .05). Fasting brought about a significant rise in the urinary percentage of urea + NH3 N, with the highest protein treatment excreting the highest percentage (P less than .05). Because plasma protein concentrations were maintained and labile protein reserves were apparently not depleted, it appears that the lowest protein diet containing 1.9 g digestible protein/W.75 was adequate, regardless of work load.

Animals↗
PubMed1985

On the role of proteases, their inhibitors and the extracellular matrix in promoting neurite outgrowth.

Using a novel method, a monoclonal antibody was produced which can directly block the activity of an extracellular matrix-associated neurite outgrowth promoting complex (Matthew and Patterson, 1983). Presumably binding at or near the active site, this antibody recognizes a determinant consisting of heparan sulfate and a larger molecule which is likely to be laminin (Matthew et al., in preparation). The antibody has been further used to localize this determinant in adult tissues in vivo. Extracellular binding is seen at sites known to promote axon regeneration in the peripheral nervous system and is not seen in the central nervous system (Matthew et al., in preparation). In investigating how neurons may modify their environment as they grow processes, we have recently found that sensory and sympathetic neurons spontaneously release a collagenase and a plasminogen activator from their distal processes and/or growth cones (Pittman, 1985). A 43 kD irreversible inhibitor of the plasminogen activator is secreted by cardiac myocytes and is found on the surfaces of cultured neurons (Pittman, 1984). This inhibitor is also released by nonneuronal cell cultures from peripheral, but not central, nerves (Pittman, unpublished). Of interest in relation to the proteoglycan neurite outgrowth promoting complex is the finding that the 43 kD inhibitor preparation binds heparin tightly and can displace laminin from its heparin binding site (Patterson and Pittman, unpublished). Thus it is possible that the protease/inhibitor system could affect outgrowth via interaction with the neurite outgrowth promoting complex in the extracellular matrix.

Animals↗
PubMed1985

Expression of noradrenergic and cholinergic traits by sympathetic neurons cultured without serum.

The ability to vary systematically the neuronal environment is one advantage afforded by the use of cell culture. Replacement of serum, a variable and undefined medium supplement, with known ingredients allows even greater control of culture conditions. We have studied biochemical and morphological properties related to neurotransmitter metabolism of rat sympathetic neurons cultured in a modified defined medium. Neuronal survival, ultrastructure, and expression of noradrenergic properties appear similar in serum-free and serum-supplemented cultures: small granular vesicles characteristic of norepinephrine storage were observed in both types of culture, and tyrosine hydroxylase activity, conversion of dopamine to norepinephrine, catecholamine production, and storage capacity are equivalent in serum-free and serum-containing cultures. Several of these properties were not exhibited at high levels in previous formulations of this defined medium. Acetylcholine production, however, was about 10-fold lower in serum-free compared to serum-supplemented cultures, consistent with the findings of lacovitti et al. (lacovitti, L., M. I. Johnson, T. H. Joh, and R. P. Bunge (1982) Neuroscience 7:2225-2239). Acetylcholine production can be induced under serum-free conditions by a previously characterized cholinergic inducing factor from heart cell conditioned medium. This responsiveness to serum-free heart cell conditioned medium indicates that serum-free cultures retain plasticity with respect to transmitter status, despite expression of noradrenergic characteristics, unlike cultured neurons of which the noradrenergic transmitter status is maintained by chronic depolarization. Thus, sympathetic neurons survive, express numerous differentiated properties, and display a novel transmitter status under serum-free conditions.

Acetylcholine↗
PubMed1985

Rat serum contains a developmentally regulated cholinergic inducing activity.

Sympathetic neurons cultured in defined medium do not develop the ability to produce acetylcholine, as do neurons grown with serum supplementation (lacovitti, L., M. I. Johnson, T. H. Joh, and R. P. Bunge (1982) Neuroscience 7:2225-2239; Wolinsky, E. J., S. C. Landis, and P. H. Patterson (1985) J. Neurosci. 5: 1497-1508). The implication that rat serum contains cholinergic inducing activity is further explored here. Dependence of cholinergic induction on serum concentration is demonstrated, and the activity is shown to reside in a macromolecular fraction. Very little cholinergic inducing activity is present in serum obtained from animals younger than 9 postnatal days. This age dependence correlates with the time of transition from noradrenergic to cholinergic transmitter status by the sympathetic innervation of the rat sweat gland in vivo (Landis, S. C., and D. Keefe (1983) Dev. Biol. 98: 349-372).

Acetylcholinesterase↗
PubMed1985

Potassium-stimulated purine release by cultured sympathetic neurons.

Environmental factors can influence cultured sympathetic neurons to acquire several different neurotransmitter phenotypes. Cholinergic and noradrenergic transmitter status can be influenced by heart cell conditioned medium, chronic depolarization (Patterson, P. H. (1978) Annu. Rev. Neurosci. 1:1-17), and rat serum (Wolinsky, E. J., and P. H. Patterson, (1985) J. Neurosci. 5:1509-1512); formation of electrical synapses can be induced by insulin (Wolinsky, E. J., H. Patterson, and A. L. Willard (1985) J. Neurosci., 5:1675-1679). Purine release has also been proposed as a possible transmission mode for sympathetic neurons (Potter, D. D., E. J. Furshpan, and S. C. Landis (1983) Fred. Proc. 42:1626-1632), and as such, it is another candidate for environmental modulation. In this report, we assess the ability of sympathetic neuron cultures grown with and without serum to release metabolically labeled tritriated purine compounds in response to depolarization. Exposure to 54 mM potassium stimulated release of adenosine, inosine, and hypoxanthine from both serum-supplemented and defined-medium cultures. However, depolarization-stimulated release of adenine nucleotides was observed only from serum-supplemented cultures and not from serum-free cultures. The release of adenine nucleotides from serum-containing cultures is affected by divalent cations in the manner expected for a neurosecretory process. The failure of serum-free cultures to release detectable adenine nucleotides raises the possibility that they do not share with, or that they differ from, serum-supplemented cultures in the purinergic aspect of the multiple transmission modes available to sympathetic neurons, and that this difference may be due to effects of the culture medium.

Adenine Nucleotides↗
PubMed1985

Insulin promotes electrical coupling between cultured sympathetic neurons.

Placing neurons in tissue culture is one way to study how environmental factors affect their differentiation. Replacement of serum-supplementation of the culture medium with defined ingredients extends the experimenter's control of the culture environment; however it also introduces additional potential influences. In this report, we confirm the observation of Higgins and Burton (Higgins, D., and H. Burton (1982) Neuroscience 7:2241-2253) of increased frequency of electrical coupling in serum-free compared to serum-supplemented cultures of rat sympathetic neurons. In addition, experiments were performed to determine whether this effect results from the removal of serum or from the addition of the defined medium components to the culture environment. The results of testing individual ingredients of the defined medium recipe adapted for use on sympathetic neurons (Bottenstein, J.E., and G. H. Sato (1979) Proc. Natl. Acad. Sci. U. S. A. 76:514-517) show that insulin is capable of inducing electrical coupling in serum-free cultures. Thus, the formation of electrical synapses by sympathetic neurons can be hormonally regulated.

Animals↗
PubMed1985

Environmental influences in the development of neural crest derivatives: glucocorticoids, growth factors, and chromaffin cell plasticity.

The neural crest gives rise to three major adrenergic cell types: sympathetic principal neurons, adrenal chromaffin cells, and small intensely fluorescent (SIF) cells. All of these derivatives synthesize and store catecholamines, but they differ in numerous other characteristics. SIF cells appear intermediate in phenotype between the other two. We have examined the role of several environmental factors in the differentiation of sympathetic principal neurons and adrenal chromaffin cells. In previous studies of young rat adrenal chromaffin cells in dissociated cell culture, differentiated characteristics such as the presence of the enzyme phenylethanolamine N-methyltransferase (PNMT), epinephrine (E) synthesis, and large catecholamine storage vesicles were not well maintained. Here we describe long-term culture of chromaffin cells which, in the presence of micromolar glucocorticoid, maintained all of these characteristics. In addition, chromaffin cells of a variety of ages were found to be dependent on glucocorticoid for long-term survival in culture. In the absence of glucocorticoid, many adrenal chromaffin cells from neonatal rats could be rescued by nerve growth factor (NGF) administration. They extended neurites, as previously described by Unsicker and colleagues (Unsicker, K., B. Krisch, U. Otten, and H. Thoenen (1978) Proc. Natl. Acad. Sci. U.S.A. 75: 3498-3502). In contrast to previous studies, however, with long-term exposure to NGF these cells became indistinguishable from mature sympathetic neurons, as judged by the following morphological and biochemical criteria: increased cell size and loss of intense CA fluorescence in their cell bodies; acquisition of characteristic neuronal ultrastructure, including morphologically specialized synapses; loss of chromaffin granules, PNMT, and E synthesis; and acquisition of neuron markers, including tetanus toxin labeling and immunoreactivity to neurofilament protein. This conversion to neurons was markedly enhanced by addition of a non-neuronal cell conditioned medium (CM) containing a neurite-promoting factor, which acted by increasing the NGF responsiveness of the chromaffin cells. Even chromaffin cells from adult rats, which are known to grow few processes in response to NGF alone, became neuronal in the presence of this CM plus NGF. While converting to neurons, adrenal chromaffin cells transiently assumed an intermediate phenotype resembling type I SIF cells, which suggests particular developmental relationships between the different cell types of the sympathoadrenal lineage.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenal Medulla↗