Role of Alpha-1 Adrenoceptor Subtypes Mediating Constriction of the Rabbit Ear Thermoregulatory Microvasculature

Material obtained from the in vitro incubation of granulocytes from saline-induced peritoneal exudates of rabbits has been shown to produce inflammation and fever in rabbits. The supernatant material from cells incubated in saline has been termed granulocytic substance (GS) and is heat-labile. Its production is temperature dependent, occurring at 37°C but not at 4°C, requires viable cells, and is inhibited by potassium ions. A similar material is liberated when cells are incubated in a more physiologic medium. Freezing and thawing of granulocytes does not release GS and the active principle cannot be obtained from the incubation of lymphocytes. GS produces a delayed inflammatory response as measured by leucocyte sticking and emigration in the rabbit ear chamber and the leakage of protein-conjugated dye at the site of intradermal injection. The former response can be accurately quantitated by calculation of the inflammatory index from reactions observed in the ear chamber. The inflammatory reaction and the properties of GS distinguish it from a variety of previously described mediators of inflammation, but GS appears to be identical with leucocytic pyrogen. The possible role of GS in delayed and protracted inflammation and its relationship to the pathogenesis of fever are discussed.

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Role of Endothelium and Adventitia on Eugenol-Induced Relaxation of Rabbit Ear Artery Precontracted by Histamine.

Journal of Smooth Muscle Research ◽

10.1540/jsmr.34.123 ◽

1998 ◽

Vol 34 (3) ◽

pp. 123-137 ◽

Cited By ~ 18

Author(s):

Hiroaki NISHIJIMA ◽

Ryuji UCHIDA ◽

Nozomi KAWAKAMI ◽

Keiichi SHIMAMURA ◽

Kenji KITAMURA

Keyword(s):

Rabbit Ear Artery ◽

Ear Artery ◽

Rabbit Ear

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DiverseBorrelia burgdorferiStrains in a Bird-Tick Cryptic Cycle

Applied and Environmental Microbiology ◽

10.1128/aem.02479-10 ◽

2011 ◽

Vol 77 (6) ◽

pp. 1999-2007 ◽

Cited By ~ 36

Author(s):

Sarah A. Hamer ◽

Graham J. Hickling ◽

Jennifer L. Sidge ◽

Michelle E. Rosen ◽

Edward D. Walker ◽

...

Keyword(s):

Small Mammals ◽

Large Scale ◽

Ixodes Scapularis ◽

Intergenic Spacer ◽

Rrna Gene ◽

Biopsy Specimens ◽

Rabbit Ear ◽

Primary Vector ◽

Vector Borne

ABSTRACTThe blacklegged tickIxodes scapularisis the primary vector of the most prevalent vector-borne zoonosis in North America, Lyme disease (LD). Enzootic maintenance of the pathogenBorrelia burgdorferibyI. scapularisand small mammals is well documented, whereas its “cryptic” maintenance by other specialist ticks and wildlife hosts remains largely unexplored because these ticks rarely bite humans. We quantifiedB. burgdorferiinfection in a cryptic bird-rabbit-tick cycle. Furthermore, we explored the role of birds in maintaining and movingB. burgdorferistrains by comparing their genetic diversity in this cryptic cycle to that found in cycles vectored byI. scapularis.We examined birds, rabbits, and small mammals for ticks and infection over a 4-year period at a focal site in Michigan, 90 km east of a zone ofI. scapularisinvasion. We mist netted 19,631 birds that yielded 12,301 ticks, of which 86% wereI. dentatus, a bird-rabbit specialist. No resident wildlife harboredI. scapularis, and yet 3.5% of bird-derived ticks, 3.6% of rabbit-derived ticks, and 20% of rabbit ear biopsy specimens were infected withB. burgdorferi. We identified 25 closely relatedB. burgdorferistrains using an rRNA gene intergenic spacer marker, the majority (68%) of which had not been reported previously. The presence of strains common to both cryptic and endemic cycles strongly implies bird-mediated dispersal. Given continued large-scale expansion ofI. scapularispopulations, we predict that its invasion into zones of cryptic transmission will allow for bridging of novel pathogen strains to humans and animals.

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Role of perivenous areolar tissue and recipient bed in the viability of venous flaps in the rabbit ear model

British Journal of Plastic Surgery ◽

10.1016/0007-1226(94)90110-4 ◽

1994 ◽

Vol 47 (1) ◽

pp. 10-14 ◽

Cited By ~ 14

Author(s):

Rick J. Smith ◽

Keizo Fukuta ◽

Michael Wheatley ◽

Ian T. Jackson

Keyword(s):

Areolar Tissue ◽

Venous Flaps ◽

Rabbit Ear

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The Effect of Serotonin Inhibition on Initial Microvessel Hemostasis and Platelet Aggregation In Vivo

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657355 ◽

1983 ◽

Vol 49 (03) ◽

pp. 173-175 ◽

Cited By ~ 6

Author(s):

D Bergqvist ◽

S Arvidsson ◽

C O Esquivel ◽

B Lindblad ◽

U Haglund

Keyword(s):

Adrenergic Receptor ◽

Formation Time ◽

Platelet Activity ◽

Receptor Affinity ◽

Rabbit Ear ◽

Rabbit Ear Chamber ◽

Plug Formation ◽

Mesenteric Microcirculation

SummaryThe role of serotonin (5-HT) in initial microvascular hemostasis is not fully understood. This study was made to evaluate the effect on hemostatic plug formation and laser-induced arteriolar microembolism of different substances which counteract the effect of 5-HT. Hemostatic plug formation time and stability was measured in the rabbit mesenteric microcirculation and laserinduced embolism in the rabbit ear chamber. Ketanserine, a selective 5-HT2-receptor blocker shortened arteriolar hemostatic plug formation time. Dihydroergotamine, an unselective blocker (with 5-HT- and α-adrenergic receptor affinity) increased venular hemostatic plug formation time and also decreased the hemostatic plug stability. Laser-induced platelet embolism was unaltered after both ketanserine and dihydroergotamine administration. The magnitude of these changes seems to exclude an important effect of 5-HT in initial microvessel hemostasis or on platelet activity.

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