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Harris GC, Williams JT. Sensitization of locus ceruleus neurons during withdrawal from chronic stimulants and antidepressants. J Pharmacol Exp Ther 1992; 261:476-83. [PMID: 1578363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The effects of chronic exposure to cocaine, amphetamine and desipramine on noradrenergic neurons in the locus ceruleus were examined using intracellular recordings in rat brain slices. Animals were treated for 2 weeks with either cocaine, amphetamine or desipramine, and all recordings were made after a 1-week withdrawal period. Cells from all three drug-treated groups showed a significant increase in sensitivity to the acute effects of cocaine and amphetamine in prolonging the time course of the noradrenaline-mediated inhibitory postsynaptic potential. At the highest cocaine and amphetamine doses tested (10 and 3 microM, respectively), the inhibitory postsynaptic potential duration was increased approximately 233% in the drug-treated groups relative to saline controls. In addition, locus ceruleus neurons from the cocaine-, amphetamine- and desipramine-treated groups showed a significant 10, 12 and 17% increase, respectively, in the maximum outward current produced by clonidine. There was also a significant increase in the behavioral sensitivity of the drug-treated animals to the sedative effects of clonidine. The mechanisms responsible for the increased sensitivity to the acute effects of cocaine, amphetamine and alpha-2 agonists may play a role in the withdrawal response to psychostimulants.
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Eglen RM, Harris GC, Ford AP, Wong EH, Pfister JR, Whiting RL. The action of (+/-)L-660,863 [(+/-)3-(3-amino-1,2,4-oxadiazole-5-yl)-quinuclidine] at muscarinic receptor subtypes in vitro. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1992; 345:375-81. [PMID: 1620240 DOI: 10.1007/bf00176613] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
1. The muscarinic pharmacology of a novel oxadiazole muscarinic agonist, (+/-) L-660,863, [+/-3-(3-amino-1,2,4-oxadiazole-5-yl)-quinuclidine] has been studied using pharmacological, radioligand binding and biochemical techniques, in vitro. 2. In isolated tissue experiments, (+/-)L-660,863 was a more potent agonist than carbachol in all preparations studied, being most potent at muscarinic receptors mediating negative chronotropy in guinea-pig right, spontaneously beating atria and least potent at receptors mediating contractions in canine saphenous vein and endothelial denuded rabbit aorta (-log EC50 values were 8.8, 6.6 and 6.3, respectively. The apparent affinities (-log KA) of (+/-)L-660,863) estimated by receptor inactivation, showed some selectivity toward the atrial M2 muscarinic receptor (-log KA = 7.6) in comparison to the M1 or M3 muscarinic receptors (-log KA = 5.4 and 6.2) respectively. This degree of selectivity was also observed in competition radioligand binding studies. 3. At M3 muscarinic receptors mediating inositol phosphates (IPs) accumulation in longitudinal muscle of guinea-pig ileum, the potency of (+/-)L-660,863 (-log EC50 value = 6.2) was similar to the apparent affinity calculated at M3 muscarinic receptors in the functional studies (see above). In contrast, at muscarinic receptors mediating IPs accumulation in guinea-pig atria and ventricles, the potency for (+/-)L-660,863 (-log EC50 = 6.2 and 6.4, respectively) was lower than the apparent affinity calculated at M2 muscarinic receptors from inotropic and binding studies in cardiac tissue (see above).(ABSTRACT TRUNCATED AT 250 WORDS)
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Harris GC, Williams JT. Transient homologous mu-opioid receptor desensitization in rat locus coeruleus neurons. J Neurosci 1991; 11:2574-81. [PMID: 1651377 PMCID: PMC6575524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Opioid agonists hyperpolarize neurons of the locus coeruleus (LC) in the slice preparation. When opioids were applied at concentrations that caused a maximum hyperpolarization, the membrane potential hyperpolarized to a peak (about 30 mV) in the first minute and then declined over a period of 5 min. In addition, following the washout, the amplitude of the hyperpolarization induced by a lower concentration of opioid was significantly reduced as compared to control. The original response to both the low and the high concentrations of opioid recovered after removal of opioids for about 20 min. The decline in response, termed "acute desensitization," was observed only with concentrations of opioids that caused a maximum hyperpolarization and was dependent on the concentration of opioid applied (EC50 for [Met5]-enkephalin (ME), between 3 and 5 microM). The response to ME (300 nM) was reduced to 6% of control following washout of a 5-min application of ME (30 microM), whereas the response to noradrenaline (300 nM) was reduced to 75% of control. The acute desensitization therefore was selective for the opioid receptor with marginal cross-desensitization to the alpha 2-adrenoceptor-mediated hyperpolarization. The desensitization still occurred following treatment with beta-chlornaltrexamine (beta-CNA), to decrease receptor reserve, as well as in cells taken from animals treated chronically with morphine. The mechanism for the acute desensitization was investigated using agents thought to alter kinase activity. This acute desensitization may represent an initial stage in the development of tolerance produced by chronic administration of opioids.
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Harris GC, Fitzgerald RD. Locus coeruleus involvement in the learning of classically conditioned bradycardia. J Neurosci 1991; 11:2314-20. [PMID: 1869918 PMCID: PMC6575500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Opioid agonists are known to inhibit the activity of locus coeruleus (LC) neurons. In this study, microinjections of the mu-opioid agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO; 1.6 microM) bilaterally into the LC caused a significant impairment in the development of a heart-rate (HR) conditioned response (CR). The adverse effect of DAMGO on the HR CR could be reversed with naltrexone pretreatment. Microinjections of DAMGO into the periaqueductal gray, parabrachial nucleus, or fourth ventricle structures 1-2 mm away from the LC had no effects on the development of an HR CR. We conclude that central noradrenergic activity as mediated by the LC is critically involved in the learning and retention of conditioned cardiovascular responses.
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Eglen RM, Harris GC, Taylor M, Pfister JR, Whiting RL. Characterization of muscarinic receptors mediating release of epithelial derived relaxant factor (EpDRF) in guinea-pig isolated trachea. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 1991; 344:29-35. [PMID: 1775190 DOI: 10.1007/bf00167379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Muscarinic receptors mediating the release of epithelial derived relaxant factor (EpDRF) have been studied by using both contractions of the guinea-pig tracheal strip (with epithelium intact or denuded) or a coaxial bioassay assembly (rat anococcygeus-recipient; guinea-pig trachea-donor tissue). Indomethacin (1 microM/1) and physostigmine (0.1 microM/1) were both present throughout the study. In the tracheal strip studies, the potencies and maximal effects of all agonists studied (acetylcholine, arecoline, bethanechol, carbachol, (+)cis-dioxolane, ethoxyethyltrimethylammonium, L-660,863, (+/-)methacholine and OXA-22) were not affected or were only slightly (but significantly) reduced by removal of the epithelium. The -log KB for the muscarinic antagonists, atropine, pirenzepine, methoctramine and 4-DAMP (4-diphenyl-acetoxy-N-methylpiperidine) were also not affected and the -log KB values were consistent with M3 muscarinic receptor function. However, the -log KB value of para-fluoro-hexahydro-siladifendol (p-F-HHSiD) was significantly (P less than 0.05) increased upon epithelial denudation (epithelium intact, 7.1; epithelium removed, 7.6). The coaxial bioassay assembly provided more convincing evidence for release of EpDRF in that all muscarinic agonists studied caused relaxations of a precontracted anococcygeus tissue. These relaxations were observed only in the presence of a tracheal tube possessing an intact epithelium. The rank order of potencies for agonists at receptors mediating EpDRF dependent relaxation were similar to those estimated at receptors causing contraction. These data suggested that a substantial receptor reserve was associated with the receptors mediating both EpDRF release and contraction.(ABSTRACT TRUNCATED AT 250 WORDS)
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Delee JA, Harris GC, Macy LB. Research note: the in vitro responses of vaginal tissue and chicken spermatozoa to glycerol. Poult Sci 1991; 70:1441-3. [PMID: 1886850 DOI: 10.3382/ps.0701441] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The fertilizing ability of glycerolized spermatozoa is apparently lost due to reactions between glycerol, spermatozoa, and vaginal tissue. Two experiments were conducted to determine the feasibility of using in vitro cultures to quantitatively assess these reactions. In the first experiment, vaginal slices alone, unglycerolized semen, and vaginal slices plus semen, all in a phosphate-buffered saline were studied. The media were separated into 14 fractions using HPLC and the absorbance of each fraction was measured at 0 and 1 h of incubation. In a second experiment the changes in absorbance of these fractions were examined for unglycerolized and glycerolized semen in vaginal cultures. When unglycerolized semen was added to the vaginal cultures, Fraction 55 appeared in significantly greater absorbance than in vaginal tissue or semen alone. The opposite occurred for Fraction 57, which decreased in absorbance after 1 h of incubation in semen-vaginal culture. Fraction 57 was increased in absorbance in the presence of glycerol in the semen-vaginal culture. Glycerol appears to block the appearance of Fraction 55 in the normal semen-vaginal reaction. This reaction may be responsible for the deleterious effects of glycerol on spermatozoal survival in vivo.
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Harris GC, Fitzgerald RD. Effects of centrally administered anxiolytic agents on classically conditioned bradycardia. Behav Neurosci 1991. [PMID: 1673847 DOI: 10.1037//0735-7044.105.1.134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Rats received infusions of the opioid peptide D-Ala2-Met-enkephalinamide (DALA, 10 micrograms), the alpha 2-noradrenergic agonist clonidine (CLON, 3 micrograms), UK14,304 (UK, 5 micrograms), the corticotropin-releasing factor (CRF) antagonist alpha-helical CRF (9-41) (alpha-HEL, 25 micrograms), or saline in the rostral fourth ventricle. The DALA, CLON, and UK groups showed no evidence of a heart rate (HR) conditioned response (CR) during conditioning, after antagonist administration, or on a nondrug test 48 hr after conditioning. These three groups showed the development of normal CRs when later retrained without drugs. The alpha-HEL group showed an enhanced CR. During a subsequent startle test, the presence of a conditioned stimulus resulted in a pronounced suppression of startle in the SAL and alpha-HEL groups but had no effects on startle in the DALA, CLON, and UK groups. The results indicate an important role for fourth ventricle structures containing opioid and alpha 2 receptors in the learning of an HR CR.
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Harris GC, Fitzgerald RD. Effects of centrally administered anxiolytic agents on classically conditioned bradycardia. Behav Neurosci 1991; 105:134-40. [PMID: 1673847 DOI: 10.1037/0735-7044.105.1.134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Rats received infusions of the opioid peptide D-Ala2-Met-enkephalinamide (DALA, 10 micrograms), the alpha 2-noradrenergic agonist clonidine (CLON, 3 micrograms), UK14,304 (UK, 5 micrograms), the corticotropin-releasing factor (CRF) antagonist alpha-helical CRF (9-41) (alpha-HEL, 25 micrograms), or saline in the rostral fourth ventricle. The DALA, CLON, and UK groups showed no evidence of a heart rate (HR) conditioned response (CR) during conditioning, after antagonist administration, or on a nondrug test 48 hr after conditioning. These three groups showed the development of normal CRs when later retrained without drugs. The alpha-HEL group showed an enhanced CR. During a subsequent startle test, the presence of a conditioned stimulus resulted in a pronounced suppression of startle in the SAL and alpha-HEL groups but had no effects on startle in the DALA, CLON, and UK groups. The results indicate an important role for fourth ventricle structures containing opioid and alpha 2 receptors in the learning of an HR CR.
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Williams JT, Bobker DH, Harris GC. Synaptic potentials in locus coeruleus neurons in brain slices. PROGRESS IN BRAIN RESEARCH 1991; 88:167-72. [PMID: 1726025 DOI: 10.1016/s0079-6123(08)63806-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neurons of the locus coeruleus (LC) fire action potentials spontaneously in vitro in the absence of any stimulation. This spontaneous activity is thought to arise from intrinsic membrane properties that include a balance between at least two ion conductances. One is a persistent inward sodium current that is active near the threshold for action potential generation. The second is a calcium-dependent potassium current that is activated following the entry of calcium during the action potential, is responsible for the after-hyperpolarization following the action potential, and decays over a period of 1-2 sec following the action potential. The spontaneous activity of LC neurons can be altered by both excitatory and inhibitory synaptic inputs. One excitatory input has been described that is mediated by glutamate receptors of both the non-NMDA and NMDA subtypes. Inhibitory synaptic potentials include those mediated by GABA (acting on GABAA-receptors), glycine (acting on a strychnine-sensitive receptor) and noradrenaline (acting on alpha 2-adrenoceptors). The presence of synaptic potentials mediated by these transmitters, studied in vitro, correlate with studies made in vivo and with histochemical identification of synaptic inputs to the locus coeruleus.
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Spreen SW, Harris GC, Macy LB. Contraceptive action of glycerol on chicken spermatozoa in oviducal organ-slice cultures. Poult Sci 1990; 69:1759-63. [PMID: 2263552 DOI: 10.3382/ps.0691759] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Chicken spermatozoa in diluent with and without glycerol were evaluated after coculture with oviducal tissues. The motility of glycerolized (G) spermatozoa was lower in the cultures of vaginal tissue than in uterine tissue. The percentage of dead, G spermatozoa increased in cultures of the vagina and uterus but not in infundibulum cultures. Glycerol significantly increased the percentage of dead spermatozoa in both vaginal and uterovaginal cultures when compared to nonglycerolized spermatozoa in the same cultures. The percentage of dead G spermatozoa was higher for semen in vaginal culture than in uterovaginal culture. Uterovaginal tissue appeared to protect spermatozoa from some of the detrimental effects of glycerol. Incubation time had a significant detrimental effect on motility and percentages of dead and abnormal spermatozoa regardless of semen or tissue treatment.
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Nelson TS, Harris GC, Kirby LK, Johnson ZB. Effect of calcium and phosphorus on the incidence of leg abnormalities in growing broilers. Poult Sci 1990; 69:1496-502. [PMID: 2247411 DOI: 10.3382/ps.0691496] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Experiments were conducted to determine the effect of various dietary levels of Ca and P on growth and leg abnormalities in broiler cockerels fed corn and soybean meal diets varying in Ca and P content. Experiment 1 was a 2 x 4 factorial arrangement utilizing .77 and .97% Ca and .33, .38, .43, and .48% available (non-phytate) P (AP). The higher level of Ca reduced the growth rate of chicks fed low levels of AP. Neither Ca nor AP affected the incidence of crooked legs or dyschondroplasia. Increasing AP to .43% increased (P less than .05) the percentage of bone ash and bone weight. In Experiment 2, chicks were reared for 3 wk on diets containing either .40 or .50% AP. From 3 to 6 wk of age, the chicks were fed diets containing from .25 to .50% AP. The Ca:AP ratios were 2:1 in all diets. The level of AP in diets fed to 3 wk of age had no influence on chick growth, the incidence of crooked legs, or dyschondroplasia in either the starting or growing period. In Experiment 3, the chicks were reared in environmental chambers and from 3 to 6 wk of age and exposed to either constant temperature (27 C) and relative humidity (RH) (50%) or cyclic temperature (27 to 38 C) and RH (80 to 50%). The chicks were fed diets containing either .30% AP and .60% CA or .45% AP and .90% Ca from 3 to 6 wk of age. Cyclic temperature and higher RH depressed growth (P less than .05) but had no effect on the incidence of weak legs or dyschondroplasia.
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Bayyari GR, Cook JR, Harris GC, Macy LB, Slavik MF, Skeeles JK. The evaluation of chicken spermatozoa using fluorescent staining in a 96-well format. Poult Sci 1990; 69:1602-5. [PMID: 1701052 DOI: 10.3382/ps.0691602] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
An efficient method for the evaluation of spermatozoa using the fluorescent stains carboxyfluorescein diacetate and propidium iodide and an automated fluorescence concentration analyzer was adapted for chicken semen. Arbitrary fluorescence units representing either live or dead spermatozoa were strongly correlated with percentage of added dead spermatozoa and with the direct fluorescent microscope counts of live, dead, and damaged cells.
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Macy LB, Harris GC, DeLee JA, Waldroup PW, Izat AL, Gwyther MJ, Eoff HJ. Effects of feeding lasalocid on performance of broilers in moderate and hot temperature regimens. Poult Sci 1990; 69:1265-70. [PMID: 2235842 DOI: 10.3382/ps.0691265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Three trials were conducted in environmental chambers to study the effects of feeding lasalocid on broiler performance. Birds were randomly assigned at 31 or 35 days of age to one of four treatment groups: hot cyclic (26.7 to 37.8 C and 90 to 40% RH) with basal diet; hot cyclic with lasalocid diet (88 mg/kg); moderate constant (21 C and 50% RH) with basal diet; or moderate constant with lasalocid diet. All birds were killed and processed 2 wk after the start of each trial. Percentage of carcass yield and fat pad weight were determined. In the moderate temperature regimen, lasalocid feeding caused a depression in the 2nd wk gain (469 versus 486 g) but not in the final 2-wk gain. In the hot temperature regimen, birds fed lasalocid gained significantly more weight in the 2nd wk than those fed the basal diet (341 g versus 325 g) and had a significantly better feed conversion in the 2nd wk (2.04 versus 2.61) and overall (2.07 versus 2.32) than those fed the basal diet.
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Harris GC, Fitzgerald RD. Impaired learning of classically conditioned bradycardia in rats following fourth ventricle administration of D-ala2-methionine-enkephalinamide. Behav Neurosci 1989; 103:77-83. [PMID: 2923679 DOI: 10.1037/0735-7044.103.1.77] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Prior to differential classical conditioning on two successive days, three groups of rats received an infusion (10 micrograms) of either the opioid peptide D-alanine2-methionine-enkephalinamide (DALA), DALA plus naltrexone (5 micrograms), or saline into the rostral region of the fourth ventricle. A fourth group, which served as a control to help localize DALA's site of action, received an infusion of DALA (10 micrograms) into the brain stem area on the floor of the ventricle. The group given DALA alone in the ventricle showed no evidence of a heart rate conditioned response (CR) either during conditioning or during a nondrug test session given 2 days after conditioning. Interference with the CR by DALA was reversed by the concomitant infusion of naltrexone. The control group given DALA in the brain stem developed a normal CR. It was suggested that DALA-induced opioid-receptor activity in the region of the periaqueductal/periventricular gray or locus coeruleus region of the ventricle may have prevented the learning of a CR. This could have occurred through a blunting of the emotional aftereffects of the unconditioned stimulus or through interference with projection pathways to other areas.
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Harris GC, Fitzgerald RD. Impaired learning of classically conditioned bradycardia in rats following fourth ventricle administration of D-Ala2-methionine-enkephalinamide. Behav Neurosci 1989. [PMID: 2923679 DOI: 10.1037//0735-7044.103.1.77] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Prior to differential classical conditioning on two successive days, three groups of rats received an infusion (10 micrograms) of either the opioid peptide D-alanine2-methionine-enkephalinamide (DALA), DALA plus naltrexone (5 micrograms), or saline into the rostral region of the fourth ventricle. A fourth group, which served as a control to help localize DALA's site of action, received an infusion of DALA (10 micrograms) into the brain stem area on the floor of the ventricle. The group given DALA alone in the ventricle showed no evidence of a heart rate conditioned response (CR) either during conditioning or during a nondrug test session given 2 days after conditioning. Interference with the CR by DALA was reversed by the concomitant infusion of naltrexone. The control group given DALA in the brain stem developed a normal CR. It was suggested that DALA-induced opioid-receptor activity in the region of the periaqueductal/periventricular gray or locus coeruleus region of the ventricle may have prevented the learning of a CR. This could have occurred through a blunting of the emotional aftereffects of the unconditioned stimulus or through interference with projection pathways to other areas.
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Sainis JK, Merriam K, Harris GC. The Association of d-Ribulose- 1,5-Bisphosphate Carboxylase/Oxygenase with Phosphoribulokinase. PLANT PHYSIOLOGY 1989; 89:368-74. [PMID: 16666540 PMCID: PMC1055845 DOI: 10.1104/pp.89.1.368] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
When Ribulose- 1,5-bisphosphate carboxylase/oxygenase was purified from spinach leaves (Spinacia oleracea) using precipitation with polyethylene glycol and MgCl(2) followed by DEAE cellulose chromatography, 75% of phosphoribulokinase and 7% of phosphoriboisomerase activities copurified with ribulose- 1,5-bisphosphate carboxylase/oxygenase. This enzyme preparation showed ribose-5-phosphate and ribulose-5-phosphate dependent carboxylase and oxygenase activities which were nearly equivalent to its corresponding ribulose- 1,5-bisphosphate dependent activity. The ribose-5-phosphate and ribulose-5-phosphate dependent reaction rates were stable and linear for much longer time periods than the ribulose- 1,5-bisphosphate dependent rates. When sucrose gradients were used to purify ribulose- 1,5-bisphosphate carboxylase/oxygenase from crude stromal extracts, phosphoribulokinase was found to cosediment with ribulose- 1,5-bisphosphate carboxylase. Under these conditions most of the phosphoriboisomerase activity remained with the slower sedimenting proteins. Ammonium sulfate precipitation resulted in separation of the ribulose- 1,5-bisphosphate carboxylase peak from phosphoribulokinase peak. Crude extracts of peas Pisum sativum and spinach contained 0.725 to 0.730 milligram of phosphoribulokinase per milligram of chlorophyll, respectively, based on an enzyme-linked immunosorbent assay.
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Stilborn HL, Harris GC, Bottje WG, Waldroup PW. Ascorbic acid and acetylsalicylic acid (aspirin) in the diet of broilers maintained under heat stress conditions. Poult Sci 1988; 67:1183-7. [PMID: 3217308 DOI: 10.3382/ps.0671183] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Male broiler chicks were grown to 21 days of age under normal conditions, then placed in environmental chambers maintained under constant (24 C) or cyclic (24 to 35 C) heat conditions. Chicks were acclimated for 1 wk on a standard grower basal diet. Standard grower basal diets were fortified with 0, 125, 250, 500, or 1,000 ppm coated ascorbic acid (AA) or 0, 125, 250, or 500 ppm acetylsalicylic acid (ASA). Test diets were fed for 14 days in two separate studies. Cyclic heat conditions reduced feed intake and significantly reduced weight gains in both trials. Feed efficiency was not significantly affected by heat stress. Neither AA or ASA had beneficial effects on broiler growth or feed efficiency.
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Latorre JR, Harris GC, Johnson ZB. Influence of storage container for frozen-thawed chicken semen and frequency of insemination on fertility and its duration. Poult Sci 1988; 67:333-5. [PMID: 3380778 DOI: 10.3382/ps.0670333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Pooled semen was diluted with Lake's solution containing 10.8% (v/v) glycerol. Aliquots of 1.2 mL and .5 mL were transferred to 1.8-mL capacity plastic vials and .5-mL capacity plastic straws, respectively. Semen was processed at 5 C, frozen by cooling at a rate of 3 C/min to -35 C, then plunged in liquid nitrogen. Samples were thawed at 5 C, diluted stepwise, centrifuged, and resuspended with nonglycerolized diluent at 5 C. Fertility and its duration were measured after single or double (insemination on 2 consecutive days) insemination. No significant differences were found in fertility percentages between semen samples frozen and stored in the two types of containers. However, fertility percentages were significantly higher for eggs laid on Days 2 to 5 after double insemination than for eggs laid after single insemination. No such differences were noted in the fertility of eggs laid on Days 2 to 7. Duration of fertility was significantly longer for semen frozen in plastic vials than for semen frozen in straws.
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Latorre JR, Harris GC, Skeeles JK, Johnson ZB. Effects of glycerol on chicken spermatozoa incubated in vitro at 41 C in oviducal and embryonic cell cultures. Poult Sci 1988; 67:135-40. [PMID: 3375168 DOI: 10.3382/ps.0670135] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Two experiments were conducted to determine the effects of glycerol on the quality and survival of spermatozoa in an in vitro system at 41 C in the presence of oviducal and other tissue cultures. The motility and percentages of abnormal and dead spermatozoa of glycerolized semen were significantly affected in a positive way by the presence of living cells. The most negative effect of glycerol on semen quality was observed with semen incubated in the tissue culture medium alone. Aspartate aminotransferase activity in the culture fluid revealed a harmful effect of glycerol on spermatozoa and culture cells.
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Harris GC, Gibbs PB, Ludwig G, Un A, Sprengnether M, Kolodny N. Mannose metabolism in corn and its impact on leaf metabolites, photosynthetic gas exchange, and chlorophyll fluorescence. PLANT PHYSIOLOGY 1986; 82:1081-9. [PMID: 16665138 PMCID: PMC1056262 DOI: 10.1104/pp.82.4.1081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
When intact corn leaves were provided millimolar concentrations of d-mannose through the transpiration stream photosynthesis was inhibited; 5.7 millimolar resulted in a 50% inhibition of the carbon exchange rate. This inhibition was partially reversible by the addition of orthophosphate to the feeding solution. Mannose metabolism by corn leaves was limited in that it did not act as a resource for sucrose or starch synthesis. Mannose 6-phosphate accumulated in the leaf tissues and was slowly metabolized by a pathway involving mannose 1-phosphate. Correlated with the mannose-6-phosphate accumulation were decreases in ATP, orthophosphate, sucrose, and phosphoenolpyruvate and increases in starch and maltose. When provided in the transpiration stream mannose had access to both mesophyll and bundle sheath cells. Mannose feeding led to oscillations in steady state chlorophyll fluorescence emission (680 nanometers) and an elimination of the Kautsky effect during fluorescence induction. Pyridoxal 5-phosphate and 2,4-dinitrophenol were found to be inhibitors of CO(2) exchange when provided in the transpiration stream of intact corn leaves. However, Pyridoxal 5-phosphate induced a quenching of steady state fluorescence while 2,4-dinitrophenol led to an increase in fluorescence emission.
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Sainis JK, Harris GC. The association of ribulose-1,5-bisphosphate carboxylase with phosphoriboisomerase and phosphoribulokinase. Biochem Biophys Res Commun 1986; 139:947-54. [PMID: 3021158 DOI: 10.1016/s0006-291x(86)80269-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
RuBPCase from peas showed Ribose-5-phosphate and Ribulose-5-phosphate dependent CO2 fixation when purified on sucrose gradients or by conventional methods. If purification was done in the presence of 20 mM MgCl2 and 20-25 mM NaHCO3 RuBPCase showed higher Ribose-5-phosphate and Ribulose-5-phosphate dependent CO2 fixation rates. Partially purified phosphoriboisomerase, phosphoribulokinase and RuBPCase from spinach could be reassociated in vitro.
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Latorre JR, Harris GC, Nelson TS, Sexton KJ. Effects of adding acid or base to the diet on semen of heat-stressed, aging broiler breeder males. Poult Sci 1986; 65:589-91. [PMID: 3010267 DOI: 10.3382/ps.0650589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Males were fed breeder basal diet, basal diet + .67 g NaHCO3, + .43 g NH4Cl, or + .86 g NH4Cl/100 g basal and exposed to diurnal cyclic temperatures of 23.9 to 35 C in chambers from 24 to 54 weeks of age. Males fed basal diet + NaHCO3 or .43 g NH4Cl were significantly heavier in body weight by 32 to 39 weeks of age than males on basal diet. Males fed the NaHCO3 diet produced significantly more semen in the first 16 weeks than males on basal diet. No differences were found in percent packed sperm value (PSV), percent dead sperm, or percent abnormal sperm between semen of males fed NaHCO3 diet and basal diet. Spermatozoal motility was significantly higher for semen of males fed NaHCO3 or NH4Cl diets during the 32- to 39-week age period.
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Harris GC, Benson JA, Sellers RS. The influence of daylength, body weight, and age on the reproductive ability of broiler breeder cockerels. Poult Sci 1984; 63:1705-10. [PMID: 6483735 DOI: 10.3382/ps.0631705] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
June-hatched broiler breeder cockerels of two strains were evaluated for reproductive performance in mating pens from 22 to 48 weeks of age. Two light programs with maximum daily daylengths of 15.5 or 16.5 hr were studied. An increase in the light day to 16.5 hr did not significantly affect the male reproductive traits except in number of completed matings and percent packed sperm volume (PSV). The males on 16.5 hr of light had significantly fewer completed matings than did the males on 15.5 hr. Strain 1 males on 16.5 hr produced significantly more spermatozoa at 35 and 40 weeks of age than males on 15.5 hr of light. Male body weights of both strains were significantly lower at 30 weeks of age on the longer daylength. Body weights of cockerels in all treatment groups increased with aging. The range in male body weight markedly influenced the percentage of producing cockerels with aging. During the late egg cycle, the number of producing males increased as body weight increased. The overall mean age of peak in the percentage of males in semen production was 44 weeks of age, which was 7 weeks later than peak egg production. Hatchability was significantly lower for male Strain 2, which had a higher percent PSV and a higher number of attempted matings than did Strain 1. Body weight was significantly correlated with male vent feather-wear at all ages and with the percentage of producing males at 48 weeks of age. The percentage of producing males was correlated with vent feather-wear, evert score, semen volume, and PSV. These results emphasize the importance of body weight selection for optimum breeding flock performance.
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Harris GC, Goto K. Carbonic anhydrase activity of the reproductive tract tissues of aged male fowls and its relationship to semen production. JOURNAL OF REPRODUCTION AND FERTILITY 1984; 70:25-30. [PMID: 6420554 DOI: 10.1530/jrf.0.0700025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A significant positive correlation was found between the carbonic anhydrase activity of the testes or ductus deferens and the volume of semen, spermatozoa or seminal plasma per collection. No relationship was found between the carbonic anhydrase activity of tissue from the epididymal region and semen production. The intramuscular injection of greater than 25 mg acetazolamide/kg body weight, a known carbonic anhydrase inhibitor, significantly reduced the carbonic anhydrase activity in the testes, epididymides and ductus deferens. As the dose was increased, the carbonic anhydrase activity of the reproductive tract tissues decreased in a linear manner. The reduction in carbonic anhydrase activity was associated with significantly lower volumes of semen, spermatozoa and seminal plasma per collection.
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Harris GC, Cheesbrough JK, Walker DA. Effects of mannose on photosynthetic gas exchange in spinach leaf discs. PLANT PHYSIOLOGY 1983; 71:108-11. [PMID: 16662766 PMCID: PMC1065994 DOI: 10.1104/pp.71.1.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
When mannose is provided in the transpiration stream to spinach (Spinacia oleracea) leaf discs, a series of specific and nonspecific changes occur in CO(2) and H(2)O vapor exchange as a function of feeding time. The initial increases in apparent photosynthesis and transpiration are nonspecific effects due to osmotic changes leading to passive stomatal opening. The mannose-specific effects are: (a) time-dependent changes in the CO(2) concentration required for saturation; (b) complex kinetics of the inhibition of CO(2) assimilation dependent on CO(2) and O(2) concentrations and the duration of feeding (high CO(2) and low O(2) lead to rapid inhibitions of photosynthesis); (c) elimination of the capacity of 2% O(2) to stimulate photosynthesis; and (d) oscillations in the CO(2) exchange rate following transitions from 20% to 2% O(2). The mannose-specific effects are reversible by orthophosphate. The mannose-dependent changes in gas exchange are attributed to altered [ATP]/[ADP] ratios.
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