Opposing effects of ethanol and nicotine on hippocampal calbindin-D28k expression.

Long-term ethanol exposure produces multiple neuroadaptations that likely contribute to dysregulation of Ca(2+) balance and neurotoxicity during ethanol withdrawal. Conversely, nicotine exposure may reduce the neurotoxic consequences of Ca(2+) dysregulation, putatively through up-regulation of the Ca(2+)-buffering protein calbindin-D(28k). The current studies were designed to examine the extent to which 10-day ethanol exposure and withdrawal altered calbindin-D(28k) expression in rat hippocampus.

Behaviour and welfare of individual laying hens in a non-cage system.

1. A leg band containing a transponder was fitted to 80 birds in a perchery containing 1,000 birds. 2.

N-n-alkylnicotinium analogs, a novel class of nicotinic receptor antagonists: interaction with alpha4beta2* and alpha7* neuronal nicotinic receptors.

The current study demonstrates that N-n-alkylnicotinium analogs with increasing n-alkyl chain lengths from 1 to 12 carbons have varying affinity (Ki = 90 nM-20 microM) for S-(-)-[3H]nicotine binding sites in rat striatal membranes. A linear relationship was observed such that increasing n-alkyl chain length provided increased affinity for the alpha4beta2* nicotinic acetylcholine receptor (nAChR) subtype, with the exception of N-n-octylnicotinium iodide (NONI). The most potent analog was N-n-decylnicotinium iodide (NDNI; Ki = 90 nM).

Effects of prolonged nicotinic ligand exposure on function of heterologously expressed, human alpha4beta2- and alpha4beta4-nicotinic acetylcholine receptors.

Effects of prolonged nicotinic ligand exposure on the function of human alpha4beta2- and alpha4beta4-nicotinic acetylcholine receptor (nAChR) subtypes were studied using receptors heterologously expressed in SH-EP1 human epithelial cells. Magnitudes of acute, nAChR-mediated, specific 86Rb+ efflux responses to 1 mM carbamylcholine were reduced after pretreatment with specific nAChR ligands in effects that depended on pretreatment drug dose, duration of drug pretreatment, and duration of drug-free recovery. Fifty percent inhibition of alpha4beta2-nAChR function following 5 min of recovery occurred after 1 min of pretreatment with 1 mM nicotine but also after 1-h pretreatment at 10 nM nicotine.

Neurotoxic effects of the human immunodeficiency virus type-1 transcription factor Tat require function of a polyamine sensitive-site on the N-methyl-D-aspartate receptor.

Human immunodeficiency virus type-I (HIV-1) infection is often associated with neuronal loss in cortical and subcortical regions that may manifest as motor dysfunction and dementia. The function of the HIV-1 transcription protein Tat and subsequent activation of N-methyl-D-aspartate receptors (NMDAr) have been implicated in this form of neurodegeneration. However, it is unclear if Tat interacts directly with the NMDAr and the role of specific NMDAr subunit composition in mediating effects of Tat is also unclear.

Effect of frequency of the stunning current waveform on carcase and meat quality of turkeys processed in a commercial plant in the UK.

1. This study compared the effects of electrical stunning delivered using high and low frequency waveforms on carcase and meat quality of turkeys processed under commercial conditions. 2.

N-n-alkylnicotinium analogs, a novel class of nicotinic receptor antagonist: inhibition of S(-)-nicotine-evoked [(3)H]dopamine overflow from superfused rat striatal slices.

The structure of the S(-)-nicotine molecule was modified via N-n-alkylation of the pyridine-N atom to afford a series of N-n-alkylnicotinium iodide salts with carbon chain lengths varying between C(1) and C(12). The ability of these analogs to evoke [(3)H] overflow and inhibit S(-)-nicotine-evoked [(3)H] overflow from [(3)H]dopamine ([(3)H]DA)-preloaded rat striatal slices was determined. At high concentrations, analogs with chain lengths > or =C(6) evoked [(3)H] overflow.

Once weekly administration of nicotine produces long-lasting locomotor sensitization in rats via a nicotinic receptor-mediated mechanism.

Rationale: Chronic nicotine administration results in dynamic changes in neuronal function, expressed as behavioral sensitization in animals and addiction in smokers.

Objectives: The present study was undertaken to determine whether once-weekly nicotine injection produces sensitization to the locomotor-activating properties of nicotine as a result of nicotinic receptor activation.

Methods: Once weekly for 6 weeks, rats were administered (s.

Influence of prior exposure to wood shavings on feather pecking, dustbathing and foraging in adult laying hens.

It has been proposed that chicks acquire substrate preferences during an early 'sensitive' period. If a suitable substrate is absent during this period birds may develop alternative preferences for pecking at feathers. The aim of this study was to examine whether early substrate exposure has durable effects on the subsequent behaviour of adult hens.

Effect of electrical stun/kill method, interval between killing and neck cutting and blood vessels cut on blood loss and meat quality in broilers.

1. Broiler chickens were killed using either an electrical waterbath (WB system) delivering 120 mA per bird (50 Hz, alternating current, AC) for 4 s or an alternative stun/kill method (ASK system); where head-only stunning for 1 s was immediately followed by head-to-body (vent) application for 1 s (150 mA, 50 Hz sine wave AC). Within each stun/kill system, the neck was cut ventrally or unilaterally 20, 60, or 180 s after killing.

Pharmacology, distribution and development of muscarinic acetylcholine receptor subtypes in the optic tectum of Rana pipiens.

Visually evoked behaviors mediated by the frog optic tectum require cholinergic activity, but the receptor subtypes through which acetylcholine acts are not yet identified. Using quantitative autoradiography and scintillation spectrometry, we examined the binding of [3H]pirenzepine and [3H]AF-DX 384 in the laminated optic tectum of the frog. In mammalian systems, these substances bind excitatory (m1 and m3 subtypes) and inhibitory (m2 and m4 subtypes) muscarinic acetylcholine receptors, respectively.

Variation in the colour of broiler breast fillets in the UK.

1. The normal range in colour of broiler breast muscle was assessed using an objective (instrumental) measure of colour in portioned breast fillets at a commercial processing plant. In addition, the relationship between colour and ultimate muscle pH (pH(ult)) was also examined.

Broiler stunning and meat quality.

The effects of electrical and concussion stunning on meat and carcass quality of broilers were compared. Broiler chickens (n = 165) were subjected to treatments: 1) electrical stunning with no fibrillation, 2) electrical stunning with fibrillation, 3) concussion stunning with restraint, or 4) concussion stunning with no restraint. Electrical stunning (100 V, 80 mA, 50 Hz sinusoidal waveform alternating current) was applied for 3 s.

Effectiveness of different electrical stunning regimens for turkeys and consequences for carcase quality.

This study examined the effectiveness of electrical stunning of turkeys applied at 150 mA per bird utilising a range of waveform-frequency combinations. In addition, the effect of stunning treatment on subsequent carcase quality was examined. The effectiveness of stunning, as judged by time to recovery, was similar regardless of bird weight or applied stunning treatment.

Effect of very low pulsed direct currents at high frequency on the return of neck tension in broilers.

Broiler chickens were stunned electrically for one second or 10 seconds with a unipolar pulsed direct current (DC) at 550 Hz. The effectiveness of the stun was assessed from the birds' behaviour. All the birds were stunned effectively when more than 15 mA true root mean square DC was applied for either period.

The problem of broken bones during the handling of laying hens--a review.

The major welfare concern during the handling of laying hens is that of broken bones. With particular reference to the United Kingdom, this paper reviews the work that has been done to quantify the problem, to examine the causes, and to investigate factors that affect it. The number of freshly broken bones found in live birds prior to slaughter and the number of old healed breaks found at slaughter are unacceptably high.

Effectiveness of electrical stunning applied using a variety of waveform-frequency combinations and consequences for carcase quality in broiler chickens.

1. The effectiveness of electrical stunning of poultry was assessed where the recommended current of 105 mA per bird was applied using a range of waveform-frequency combinations. In addition the effect of the treatments on subsequent carcase quality was investigated.

Carcase and meat quality in ducks killed with either gas mixtures or an electric current under commercial processing conditions.

1. The feasibility of killing 7-week old Peking ducks with gas mixtures and their effects on carcase and meat quality were evaluated and compared with killing in electrical waterbath under commercial conditions. 2.

Intravenous lidocaine speeds the return of bowel function, decreases postoperative pain, and shortens hospital stay in patients undergoing radical retropubic prostatectomy.

Unlabelled: Postoperative ileus is a concern among surgical patients. Epidural anesthesia and analgesia with local anesthetics can decrease the duration of ileus. Significant systemic absorption of local anesthesia occurs during epidural use.

Carcase and meat quality in broilers either killed with a gas mixture or stunned with an electric current under commercial processing conditions.

1. Carcase and meat quality were evaluated under commercial conditions in 400 broilers either killed with a mixture of 30% carbon dioxide and 60% argon in air or stunned with a 50 Hz AC with clipped sine wave. 2.

Long-term ethanol and nicotine treatment elicit tolerance to ethanol.

Several previous studies have shown that 1 to 2 weeks of treatment with ethanol elicits tolerance to several effects produced by ethanol and cross-tolerance to nicotine-induced hypothermia. Similarly, short-term, high-dose nicotine treatment produces tolerance to nicotine and cross-tolerance to ethanol-induced hypothermia. In the studies reported here, C57BL/6 mice were force-fed ethanol, nicotine, or an ethanol/nicotine combination in the drinking water for 6 months.