Inhibition of neuronally induced relaxation of canine lower esophageal sphincter by opioid peptides

Opioid peptides have profound effects on gut motility. To assess their actions on enteric neurons regulating sphincteric smooth muscle, the ability of several opioid agonists to antagonize the neuronally induced relaxation of canine lower esophageal sphincter smooth muscle was examined. Opioid peptides selective for mu (FK 33-824) or delta [( D-Pen2,D-Pen5]enkephalin) receptors produced a concentration dependent inhibition of electrical field stimulation (EFS)-induced relaxation. In contrast, neither kappa (ketocycloclazine) or sigma (SK & F 10047) opioid agonists were potent inhibitors of EFS-induced relaxation. This inhibition was relatively selective for opioid agonists since BHT 933 (alpha 2 adrenoceptor agonist) and SK & F 89124 (D2 dopamine agonist) did not inhibit EFS-induced relaxation. Furthermore, naloxone antagonized the effects of both FK 33-824 and DPDPE. These functional data suggest that opioid receptors are present on sphincteric intrinsic inhibitory neurons and that stimulation of these neuronal receptors can regulate lower esophageal sphincter relaxation.     

Inhibition of Tuberoinfundibular Dopaminergic Neural Activity During Suckling: Involvement of μ and κ Opiate Receptor Subtypes

Previous studies have shown that mu (μ) and kappa ( κ ) opioid antagonists inhibit suckling-induced prolactin release. Prolactin responses elicited by pup suckling or opioid administration are mediated, at least in part, by suppression of dopamine (DA) release from tuberoinfundibular dopaminergic (TIDA) neurons in the hypothalamus. We examined the effects of the μ opiate receptor antagonist, β -funaltrexamine ( β -FNA), and the κ opiate receptor antagonist, nor-binaltorphimine (nor-BNI) on the activity of TIDA neurons in lactating rats. TIDA neuronal activity was determined by measuring DOPA accumulation in the caudate putamen (CP) and median eminence (ME). The effects of opioid antagonist treatment were determined in pup-deprived (low circulating prolactin levels) or pup-suckled rats (high circulating prolactin levels). The accumulation of 5-hydroxytryptophan (5-HTP) in the medial preoptic area (MPOA), the anterior hypothalamus (AH) and the median eminence (ME) was quantified as an index of serotonergic activity in the same animals for comparative purposes.     

Distribution of normal and abnormal fluid collections in the glenohumeral joint: Implications for MR arthrography

Although magnetic resonance (MR) images of the glenohumeral joint frequently demonstrate intraarticular fluid, no specific criteria have, to the authors' knowledge, been published that allow accurate assessment of the amount of fluid present. Also, despite the increasing use of MR arthrography of the shoulder, the optimal amount of intra-articular fluid that should be used with this technique has not been determined. The authors progressively distended the glenohumeral joint in six cadaveric shoulder specimens with a dilute gadopentetate dimeglumine solution and obtained MR images after injection of 2, 5, 10, 15, and 20 mL of the solution. The pattern of fluid distribution was evaluated, and these results were then used to estimate the amount of fluid that was present in the glenohumeral joint on MR images of 20 shoulders obtained in 12 asymptomatic volunteers. In 14 of these shoulders, intraarticular fluid was present; however, in none was more than 2 mL evident. Results of the cadaveric study also indicated that 15 mL of intraarticular fluid appears to be the optimal amount for MR arthrography.     

Prolonged absence status epilepticus associated with carbamazepine therapy, increased intracranial pressure, and transient MRI abnormalities.

We describe an adolescent epileptic patient who presented in nonconvulsive status epilepticus that appeared to be related to treatment with carbamazepine. The absence status, which was resistant to multiple anticonvulsants, produced increased intracranial pressure and transient abnormalities observed on MRI.     

Reliability of grip strength, walking time and button test performed according to a standard protocol

Excellent interobserver and intraobserver reliability (reproducibility) was seen for the grip strength, walking time and button test measures in 40 patients with rheumatoid arthritis (RA), when measurement was performed according to a standard protocol. Evidence of reliability, coupled with the observation that baseline measures predict longterm morbidity and mortality in individual patients, suggests that these measures might be more widely used in general rheumatologic care.     

Habitat characteristics of Coquillettidia perturbans in central Florida

Habitat characteristics were examined in two marshes and the littoral zones of two lakes in central Florida to determine their effect on the density and distribution of Coquillettidia perturbans. Larval and water samples were collected and habitat characteristics were recorded at monthly intervals for one year. Several significantly different physicochemical parameters were found between the marshes and lakeshores. Sites with dissolved oxygen less than 1.5 mg/liter (from October through May), pH less than 5.2, total alkalinity less than 6.0 mg CaCO3/liter, and orthophosphate less than 0.25 mg/liter were associated with significantly higher concentrations of Cq. perturbans. Arrow-arum, caric sedge, and maidencane were also associated with higher numbers of Coquillettidia.     

The effect of hydration water temperature on orthopedic plaster cast strength

The effect of hydration water temperature (dip water) on the strength of orthopedic casts is discussed. Three methods of testing are used in an attempt to detect any differences and also to assess their clinical relevance. It was found that warmer water produced stronger casts, however, the differences were not found to be clinically relevant. It is suggested that water temperature be chosen on the basis of considerations other than strength.     

Discriminative stimulus properties of the serotonin agonist MK 212

In an attempt to clarify the role of 5-hydroxytryptamine (5-HT) in the discriminative stimulus properties of MK 212 (6-chloro-2[1-piperazinyl]pyrazine), male Sprague-Dawley rats were trained to discriminate 0.5 mg/kg of this compound from saline. While the putative 5-HT agonists fenfluramine and m-chlorophenylpiperazine (MCPP) mimicked MK 212 in a dose-related manner, d-lysergic acid diethylamide (LSD), 8-hydroxy-2(di-n-propylamino)tetralin (8-OHDPAT), 5-methoxy-N,N-dimethyltryptamine (5-MeODMT), quipazine, Ru 24969, and 1-(m-trifluoromethylphenyl)piperazine (TFMPP) failed to substitute completely. The 5-HT₁/5-HT₂ antagonists BC 105, metergoline, and methysergide completely blocked the MK 212 cue, while the selective 5-HT₂ antagonists ketanserin and pirenperone, the dopamine antagonists haloperidol and spiperone, and the beta-noradrenergic antagonist propranolol were without effect. The substitutions of fenfluramine and MCPP for MK 212 support a role for 5-HT in the MK 212 cue; however, the lack of substitution of many other 5-HT agonists is difficult to explain. The complete antagonism by 5-HT₁/5-HT₂ but not by selective 5-HT₂, antagonists suggests the possibility that 5-HT₁ receptors mediate the stimulus properties of MK 212. Further research is needed to support this hypothesis and to investigate the relative role of 5-HT and other neurotransmitters in the stimulus effects of MK 212.Portions of this research were presented at the Meeting of the Committee on Problems of Drug Dependence Satellite Session (International Study Group Interested in Drugs as Reinforcers and the Society for the Stimulus Properties of Drugs) in Baltimore, MD (1985)     

A survey of child care workers: Implications for administrators regarding job stress and satisfaction

Child care agencies in Ohio were surveyed concerning their programs and child care workers so as to better understand factors that contribute to job stress, attrition, and satisfaction. The survey provided data regarding the population served at the agencies and the characteristics of child care workers, their services, concerns, desires, and rewards. The findings indicate that environmental variables contribute largely to perceived concern and desired changes, whereas success with children provides a prominent source of job satisfaction.