Peripheral mu-, kappa- and delta-opioid receptors mediate the hypoalgesic effect of celecoxib in a rat model of thermal hyperalgesia.

AIMS: The endogenous opioids mediate the analgesic effects of celecoxib in a model of mechanical hyperalgesia in rats. As responses to thermal stimuli may differ from those to mechanical stimuli, we have here assessed celecoxib in a rat model of thermal hyperalgesia and the possible involvement of endogenous opioids and their corresponding receptors in these effects. MAIN METHODS: Injection of carrageenan (CG) into one hind paw induced a dose-related hyperalgesia (decreased time for paw withdrawal) to thermal stimuli (infra-red light beam), over 6h. KEY FINDINGS: Celecoxib (sc) 30 min before CG (250 microg per paw) induced a dose-dependent reversal of hyperalgesia, with withdrawal times well above basal levels, characterizing development of hypoalgesia. Indomethacin (sc) reversed CG-induced hyperalgesia only to basal levels (an anti-hyperalgesic effect). Naltrexone (sc) prevented hypoalgesia after celecoxib but did not change the response to indomethacin. Local (intraplantar) injection of either a selective antagonist of mu-(beta-funaltrexamine), kappa-(nor-binaltorphimine) or of delta-(naltrindole) opioid receptors also reversed the hypoalgesic effects of celecoxib, without modifying the hyperalgesia due to CG or affecting the nociceptive thresholds in the non-injected paw. SIGNIFICANCE: Our data show that celecoxib, unlike indomethacin, was hypoalgesic in this model of thermal hyperalgesia, and that this effect was mediated by peripheral mu-, kappa- and delta-opioid receptors.

Is dermatology slipping into its anec-dotage?

In recent issues, the Archives has run a feature entitled "In the Archives a Century Ago" in which a portion of a very old article is reprinted. These articles seem often to be chosen for comic interest and make good reading, seeing how widely our forefathers missed the mark. It is even better when the author is a familiar name. How could they think such crazy things? Usually a short while after feeling so smug, one of our residents, or perhaps a visiting internist, will give me a strange look after I state some dermatologic concept and ask how we have come to such a conclusion. Sometimes, it can be tough to defend (why do so many people get "insect bite reactions" in the dead of winter?), and I am left wondering how we know what we know.

Inhibition of a model of in vitro granuloma formation by tetracyclines and ciprofloxacin. Involvement of protein kinase C.

BACKGROUND AND DESIGN: Granulomatous inflammation is a common component of many diseases. In this study the ability of commonly used antibiotics to inhibit an in vitro model of granuloma formation were studied. The effect of protein kinase C inhibition in this system was also investigated. RESULTS: Ampicillin, cephalothin, metronidazole, rifampin, isoniazide, erythromycin, and clindamycin were inactive in inhibiting granuloma formation. Tetracycline, doxycycline, minocycline, and ciprofloxacin produced dose-dependent inhibition of the granuloma model in concentrations between 10(-4) and 10(-6) mol/L. The approximate order of descending potency was doxycycline equals minocycline greater than tetracycline greater than ciprofloxacin. The same drugs were tested for the ability to inhibit protein kinase C. Drugs inactive in the granuloma model had no effect on protein kinase C activity. The tetracyclines and ciprofloxacin all caused a dose-dependent inhibition of protein kinase C activity in the same order of relative potency as was found for inhibition of granuloma formation. CONCLUSIONS: These data demonstrate a previously unappreciated activity of the tetracyclines and ciprofloxacin. Inhibition of granuloma formation helps to account for the activity of these drugs in the severest forms of inflammatory acne.

The clinical spectrum of bacillary angiomatosis.

Bacillary angiomatosis is a recently recognized bacterial infectious disease that is seen mainly in patients with the acquired immunodeficiency syndrome. Including this publication, 45 patients have been described in the medical literature. In this report we describe examples of the clinical presentations of bacillary angiomatosis and review therapeutic strategies.

Reflex sympathetic dystrophy. Occurrence of inflammatory skin lesions in patients with stages II and III disease.

Reflex sympathetic dystrophy is a poorly understood syndrome of posttraumatic pain and sympathetic nervous aberration. We have observed previously unreported cutaneous manifestations of reflex sympathetic dystrophy. Seven patients with reflex sympathetic dystrophy were referred to our institution because of skin disorders. Three had recurrent ulcerating papules, and two had reticulate hyperpigmentation. Xerosis was common, and cutaneous atrophy was infrequent. Cutaneous ulceration and reticulate hyperpigmentation are previously unappreciated aspects of reflex sympathetic dystrophy. Further investigation regarding neural influences on the skin is warranted.

Foraging differences in cattle: fecal analysis of three racial categories in a harsh environment.

Feces from three racial categories of cattle being raised together in degraded, desertic-thorn forest environment in northwestern Mexico were compared for plant epidermal cell content. There were statistically significant group differences for approximately one-third of the plant material found in the feces. The proportional fecal differences between racial categories were similar to those found previously for B-system blood types. The feces of Bos taurus-like cattle contained a greater variety of plants than did those of B indicus-like animals. The findings have implications for studies of behavioral evolution, the effects of cattle on ecology, and cattle husbandry.

Sistemas de polonização de duas espécies simpátricas de Dalechampia (Euphorbiaceae) no Amazonas, Brasil

Summary During September, 1978 observation were made near Cacau Pirêra, in the vicinity of Manaus, Amazonas, Brazil, on the pollination systems of two sympatric species of Dalechampia (Euphorbiaceae). The flowers of Dalechampia are unisexual; three pistillate and usually 9-10 staminate flowers are aggregated into a functionally bisexual inflorescence which is subtended by two large showy bracts. The two sympatric species which occur near Manaus, D. affinis and D. scandens differ from each other in time of day that the inflorescences are open for pollination, size of bracts, the distances from the flowers to the gland which secretes resin (the pollinator attractant), and the amount of resin secreted. D. affinis secretes a larger amount of resin than D. scandens, attracting Euglossa sp. and Hypanthidium nr. melanopterum. Because the distance between the gland and stigma is relatively great, only the larger bee, Euglossa, pollinates D. affinis. D. scandens secretes a smaller amount of resin and attracts only small bees, Hypanthidium nr. melanopterum, which do pollinate this small-flowered species. The attraction of different bees by such similar plant species is probably the result of the tendency for the larger bees i.e. Euglossa) to forage resin only from sources with large amounts of resin, "ignoring" inflorescences with small amounts of resin. Although both D. affinis and D. scandens are visited by Hypanthidium, the pollen flow between the two species is probably fairly low. Hypanthidium pollinates D. scandens early in the day before the inflorescences of D. affinis are open. It is too small a bee to transfer any pollen to the stigmas of D. affinis when inflorescences of that species are open in the late afternoon.

Resumo Dalechampia affinis (Euphorbiaceae) e D. scandens crescem simpaticamente nos arredores de Manaus, Amazonas, Brasil. Durante uma pesquisa, realizada em setembro de 1978, observou-se que as duas espécies diferiam uma da outra no tamanho da glândula floral que secreta resina (o atrativo do polinizador), na disposição das flores estaminadas e pistiladas na inflorescência, e no periodo do dia que as brácteas da inflorescência se abrem. Tais diferenças resultam de ser D. affinis polinizada principalmente por Euglossa (Apidae) e D. scandens principalmente por Hypanthidium (Megachilidae). Como uma conseqüência dessas diferenças há. provavelmente, pouco fluxo de pólen entre as duas espécies observadas.

Sistemas de polonização de duas espécies simpátricas de Dalechampia (Euphorbiaceae) no Amazonas, Brasil

Summary During September, 1978 observation were made near Cacau Pirêra, in the vicinity of Manaus, Amazonas, Brazil, on the pollination systems of two sympatric species of Dalechampia (Euphorbiaceae). The flowers of Dalechampia are unisexual; three pistillate and usually 9-10 staminate flowers are aggregated into a functionally bisexual inflorescence which is subtended by two large showy bracts. The two sympatric species which occur near Manaus, D. affinis and D. scandens differ from each other in time of day that the inflorescences are open for pollination, size of bracts, the distances from the flowers to the gland which secretes resin (the pollinator attractant), and the amount of resin secreted. D. affinis secretes a larger amount of resin than D. scandens, attracting Euglossa sp. and Hypanthidium nr. melanopterum. Because the distance between the gland and stigma is relatively great, only the larger bee, Euglossa, pollinates D. affinis. D. scandens secretes a smaller amount of resin and attracts only small bees, Hypanthidium nr. melanopterum, which do pollinate this small-flowered species. The attraction of different bees by such similar plant species is probably the result of the tendency for the larger bees i.e. Euglossa) to forage resin only from sources with large amounts of resin, "ignoring" inflorescences with small amounts of resin. Although both D. affinis and D. scandens are visited by Hypanthidium, the pollen flow between the two species is probably fairly low. Hypanthidium pollinates D. scandens early in the day before the inflorescences of D. affinis are open. It is too small a bee to transfer any pollen to the stigmas of D. affinis when inflorescences of that species are open in the late afternoon.

Resumo Dalechampia affinis (Euphorbiaceae) e D. scandens crescem simpaticamente nos arredores de Manaus, Amazonas, Brasil. Durante uma pesquisa, realizada em setembro de 1978, observou-se que as duas espécies diferiam uma da outra no tamanho da glândula floral que secreta resina (o atrativo do polinizador), na disposição das flores estaminadas e pistiladas na inflorescência, e no periodo do dia que as brácteas da inflorescência se abrem. Tais diferenças resultam de ser D. affinis polinizada principalmente por Euglossa (Apidae) e D. scandens principalmente por Hypanthidium (Megachilidae). Como uma conseqüência dessas diferenças há. provavelmente, pouco fluxo de pólen entre as duas espécies observadas.