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Background and Aim: Hypersensitivity to house dust mites is a common cause of atopic dermatitis in dogs. The intradermal test (IDT) identifies allergens to be included in allergen-specific immunotherapy. Common mite allergens used for IDT include single source extracts obtained from Dermatophagoides farinae or Dermatophagoides pteronyssinus or multisource extracts from multimite species (mixed mites), as well as a combination of multimite species and proteins from feces and shed skin (house dust). The objectives of the present study were to evaluate the prevalence of mite sensitivity in dogs diagnosed with atopic dermatitis in different Thailand provinces and to determine if positive test results to mite allergens aligned. Materials and Methods: Eighty-two dogs (median age [range]: 5 years [11 months-11 years]; 51 males and 31 females) diagnosed with atopic dermatitis underwent IDTs with four different mite-related allergens (D. farinae, D. pteronyssinus, mixed mites, and house dust). The skin reactions were reported on a scale of 0-4 and the reactions 2+ were considered clinically relevant. The relationship between IDT results from different allergens was determined using Pearson's correlation coefficient (r). Fisher's exact test was used to compare IDT results for different mite allergens as well as for dogs residing in Bangkok versus other provinces in Thailand. Results: The prevalence (95% confidence interval [CI]) of positive IDT results for D. farinae, D. pteronyssinus, mixed mites, and house dust in dogs with atopic dermatitis was 64.63% (52.30-74.88), 58.54% (47.12-69.32), 47.56% (36.41-58.89), and 35.37% (25.12-46.70), respectively. A moderate correlation was found in IDT results between D. pteronyssinus and house dust (r=0.514), between D. pteronyssinus and D. farinae (r=0.426), and between D. farinae and mixed mites (r=0.423). The prevalence of dogs with positive IDT results for mite allergens with mono-sensitization, bi-sensitization, tri-sensitization, and quadru-sensitization did not differ significantly between dogs residing in Bangkok (11.63%, 18.60%, 25.58%, and 16.28%) and dogs residing in other provinces (12.82%, 30.77%, 35.90%, and 10.26%). The overall sensitivity (95% CI) and specificity (95% CI) of the mixed mites test associated with atopic dermatitis in dogs were 60.32% (47.20-72.40%) and 94.70% (74.00-99.90%), respectively. The overall sensitivity (95% CI) and specificity (95% CI) of the house dust test associated with atopic dermatitis in dogs were 42.90% (30.50-56.00%) and 89.50% (66.90-98.70%), respectively. Conclusion: House dust mites are an important source of allergens for dogs with atopic dermatitis. In the present study, no significant difference in the prevalence of atopic dermatitis was found in dogs living in the urban area compared with dogs living in the countryside. Application of multisource extracts from mites for IDT revealed a higher reaction to mixed mites than that of house dust.

Aim:  In the rat, intraperitoneal injection of p -chloroamphetamine (PCA), which releases central 5-hydroxytryptamine (5-HT) from serotonergic nerve terminals, induces ejaculation, even in the absence of an estrus female or female-related smell information. It is well known that the medial preoptic nucleus (MPN) and the medial nucleus amygdala (MEA) play a major role in the control of male sexual behavior in mammals. We examined whether or not neuronal activity of the MPN and/or the MEA was associated with PCA-induced ejaculation. Methods:  Using c-Fos immunohistochemistry, we demonstrated a difference in the neural activities of the MPN and the MEA for ejaculation during copulation with an estrus female and ejaculation by PCA injection. Results:  Increased numbers of c-Fos-immunoreactive (c-Fos-IR) cells were found in the MPN and the MEA in the brains of the mating animals, whereas in the brains of the animals undergoing PCA-induced ejaculation there was no increase in the number of c-Fos-IR cells in the MPN and a small increase in the MEA. Conclusion:  Based on these results, ejaculation induced by PCA is not associated with the MPN. Moreover, the MEA is not the main act for this ejaculation. (Reprod Med Biol 2008; 7 : 37-43).