19 research outputs found
Pharmacopuncture Versus Acepromazine in Stress Responses of Horses During Road Transport
AbstractAcupuncture has been shown to have the beneficial effect of reducing stress responses in animals and humans. Pharmacopuncture is the injection of subclinical doses of drugs into acupoints to give therapeutic results without side effects. This study compared the effects of injecting the usual dose of acepromazine (ACP; 0.1 mg/kg, intramuscularly [I.M.]) with those of pharmacopuncture (1/10 ACP dose at the governing vessel 1 [GV 1] acupoint) on the stress responses of healthy horses undergoing road transport for 2.5 hours. Four different treatments were applied immediately before loading, with 8 animals/treatment: injection of saline or ACP (0.1 mg/kg, I.M.) at the base of the neck; and injection of saline or 1/10 ACP (0.01 mg/kg) at the GV 1 acupoint. The road transport increased heart rate (HR), respiratory rate, body temperature, and serum cortisol of the untreated horses (injected with saline at the base of the neck). Pharmacopuncture at GV 1 reduced the average HR and transport-induced increase in HR at unloading, without changing the other variables. On the other hand, ACP (0.1 mg/kg) produced significant sedation and reduced the transport-induced increase in respiratory rate but without preventing the stress-induced increase of cortisol. Other acupuncture points and drugs should be tested to verify the beneficial effect of this therapy to reduce stress in horses during road transport
Behavioural, endocrine and cardiac autonomic responses to a model of startle in horses
Startle is a fast response elicited by sudden acoustic, tactile or visual stimuli in a variety of animal species and in humans. The magnitude of startle response can be modulated by external and internal variables and can be a useful tool to study the sensory-motor integration in animals. Different stimuli have been used to induce startle in horses, which makes it difficult to compare the responses to these different approaches. The present study uses ultra-short-term heart rate variability (HRV) analysis to characterize the cardiac autonomic modulation, reactivity assessment and blood cortisol measurements to describe the behavioural and endocrine responses to a simple, easy to replicate, effective and safe method of startle (an umbrella is abruptly opened near the horse). The ultra-short-term (64 s) heart rate (HR) series were interpolated (4 Hz) and divided into 256 points segments then the spectra calculated (Fast Fourier Transform). The spectra were then integrated into low (LF; 0.01–0.07 Hz; Index of Cardiac Sympathetic Modulation) and high (HF; 0.07–0.50 Hz; Index of Cardiac Parasympathetic Modulation) frequency bands. Following the startle test, the HR (p = 0.0101), the power of the LF band of the cardiac interval spectrum (p = 0.0002) and the LF/HF ratio (p = 0.0066) were found to be higher, whereas the power of the HF band of the cardiac interval spectrum was found to be lower (p = 0.0002). Also, the horses showed a noticeable escape response, with latency of reaction varying from 0.28 to 1.28 s, duration of reaction ranging from 1.52 to 7.92 s and escape distance covered varying from 3.43 to 9.97 m. However, the endocrine measurements failed to reveal significant changes in the cortisol levels after the startle test. We conclude that the startle test used in the current study was effective to produce changes in behavioural parameters and cardiac autonomic modulation of the horses and can therefore be an appropriate tool for neurobiological studies. Furthermore, the use of ultra-short segments (64 s) for HRV analysis appears to be effective and promising for the detection of mental stress in horses.Instituto de Genética Veterinari
Behavioural, endocrine and cardiac autonomic responses to a model of startle in horses
Startle is a fast response elicited by sudden acoustic, tactile or visual stimuli in a variety of animal species and in humans. The magnitude of startle response can be modulated by external and internal variables and can be a useful tool to study the sensory-motor integration in animals. Different stimuli have been used to induce startle in horses, which makes it difficult to compare the responses to these different approaches. The present study uses ultra-short-term heart rate variability (HRV) analysis to characterize the cardiac autonomic modulation, reactivity assessment and blood cortisol measurements to describe the behavioural and endocrine responses to a simple, easy to replicate, effective and safe method of startle (an umbrella is abruptly opened near the horse). The ultra-short-term (64. s) heart rate (HR) series were interpolated (4. Hz) and divided into 256 points segments then the spectra calculated (Fast Fourier Transform). The spectra were then integrated into low (LF; 0.01-0.07. Hz; Index of Cardiac Sympathetic Modulation) and high (HF; 0.07-0.50. Hz; Index of Cardiac Parasympathetic Modulation) frequency bands. Following the startle test, the HR (p = 0.0101), the power of the LF band of the cardiac interval spectrum (p = 0.0002) and the LF/HF ratio (p = 0.0066) were found to be higher, whereas the power of the HF band of the cardiac interval spectrum was found to be lower (p = 0.0002). Also, the horses showed a noticeable escape response, with latency of reaction varying from 0.28 to 1.28. s, duration of reaction ranging from 1.52 to 7.92. s and escape distance covered varying from 3.43 to 9.97. m. However, the endocrine measurements failed to reveal significant changes in the cortisol levels after the startle test. We conclude that the startle test used in the current study was effective to produce changes in behavioural parameters and cardiac autonomic modulation of the horses and can therefore be an appropriate tool for neurobiological studies. Furthermore, the use of ultra-short segments (64 s) for HRV analysis appears to be effective and promising for the detection of mental stress in horses.Fil: Villas Boas, Julia Dias. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: Martins Dias, Daniel Penteado. Universidade de Sao Paulo; BrasilFil: Trigo, Pablo Ignacio. Universidade Federal do Estado do Rio de Janeiro; Brasil. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: dos Santos Almeida, Norma Aparecida. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: de Almeida, Fernando Queiroz. Universidade Federal do Estado do Rio de Janeiro; BrasilFil: de Madeiros, Magda Alves. Universidade Federal do Estado do Rio de Janeiro; Brasi
Acupuncture affects autonomic and endocrine but not behavioural responses induced by startle in horses
Startle is a fast response elicited by sudden acoustic, tactile, or visual stimuli in a variety of animals and in humans. As the magnitude of startle response can be modulated by external and internal variables, it can be a useful tool to study reaction to stress. Our study evaluated whether acupuncture can change cardiac autonomic modulation (heart rate variability); and behavioural (reactivity) and endocrine (cortisol levels) parameters in response to startle. Brazilian Sport horses (n = 6) were subjected to a model of startle in which an umbrella was abruptly opened near the horse. Before startle, the horses were subjected to a 20-minute session of acupuncture in acupoints GV1, HT7, GV20, and BL52 (ACUP) and in nonpoints (NP) or left undisturbed (CTL). For analysis of the heart rate variability, ultrashort-term (64 s) heart rate series were interpolated (4 Hz) and divided into 256-point segments and the spectra integrated into low (LF; 0.01–0.07 Hz; index of sympathetic modulation) and high (HF; 0.07–0.50 Hz; index of parasympathetic modulation) frequency bands. Acupuncture (ACUP) changed the sympathovagal balance with a shift towards parasympathetic modulation, reducing the prompt startle-induced increase in LF/HF and reducing cortisol levels 30 min after startle. However, acupuncture elicited no changes in behavioural parameters.Instituto de Genética Veterinari
The Impact of a Non-Functional Thyroid Receptor Beta upon Triiodotironine-Induced Cardiac Hypertrophy in Mice
Efeito da acupuntura nas respostas de estresse em equinos atletas submetidos a reprise de adestramento
O cavalo tem uma predisposição natural para o esporte, no entanto, o seu uso em competições pode resultar em problemas relacionados ao estresse que prejudicam seu desempenho esportivo e principalmente a sua saúde. Neste sentido é fundamental desenvolver estratégias que possam prevenir ou minimizar os efeitos deletérios do estresse. Neste sentido a acupuntura é uma técnica milenar da Medicina Tradicional Chinesa que tem sido utilizada no tratamento e prevenções de doenças relacionadas ao estresse. Desta forma, avaliamos se acupuntura pode alterar as respostas de estresse em cavalos atletas submetidos a uma prova de reprise de adestramento. Seis equinos da raça Brasileiro de Hipismo, com idade entre 6 e 8 anos, experientes em provas de adestramento, provenientes da Escola de Equitação do Exército, Rio de Janeiro, Brasil foram utilizados. O efeito da acupuntura nos pontos VG1, C7, VG20 e B52 imediatamente antes da reprise de adestramento foi avaliada através da análise do desempenho na prova, do cortisol sérico e da variabilidade da frequência cardÃaca (VFC). Para análise da VFC foi utilizado frequencÃmetro cardÃaco Polar Equineâ„¢ e as amostras de sangue foram coletadas antes e 30 minutos após o fim da reprise para análise do cortisol. O desempenho dos animais foi avaliado por juÃzes oficiais e pelos cavaleiros. Acupuntura reduziu significativamente a razão LF/HF (p < 0,0001) um Ãndice que indica o balanço simpato-vagal sugerindo que a acupuntura pode reduzir a resposta autonômica cardÃaca em situação de estresse. No entanto, a acupuntura não teve efeito significativo sobre a frequência cardÃaca, sobre os nÃveis de cortisol e sobre o desempenho avaliado pelos juÃzes e cavaleiros. Nossos estudos resultados sugerem que a acupuntura pode reduzir algumas respostas de estresse em cavalos atletas submetidos a provas de reprise de adestramento e que este efeito se deva a sua ação potencializadora da atividade vaga
Acupuncture Affects Autonomic and Endocrine but Not Behavioural Responses Induced by Startle in Horses
Startle is a fast response elicited by sudden acoustic, tactile, or visual stimuli in a variety of animals and in humans. As the magnitude of startle response can be modulated by external and internal variables, it can be a useful tool to study reaction to stress. Our study evaluated whether acupuncture can change cardiac autonomic modulation (heart rate variability); and behavioural (reactivity) and endocrine (cortisol levels) parameters in response to startle. Brazilian Sport horses (n=6) were subjected to a model of startle in which an umbrella was abruptly opened near the horse. Before startle, the horses were subjected to a 20-minute session of acupuncture in acupoints GV1, HT7, GV20, and BL52 (ACUP) and in nonpoints (NP) or left undisturbed (CTL). For analysis of the heart rate variability, ultrashort-term (64 s) heart rate series were interpolated (4 Hz) and divided into 256-point segments and the spectra integrated into low (LF; 0.01–0.07 Hz; index of sympathetic modulation) and high (HF; 0.07–0.50 Hz; index of parasympathetic modulation) frequency bands. Acupuncture (ACUP) changed the sympathovagal balance with a shift towards parasympathetic modulation, reducing the prompt startle-induced increase in LF/HF and reducing cortisol levels 30 min after startle. However, acupuncture elicited no changes in behavioural parameters
The Impact of a Non-Functional Thyroid Receptor Beta upon Triiodotironine-Induced Cardiac Hypertrophy in Mice
Background/Aims: Thyroid hormone (TH) signalling is critical for heart function. The heart expresses thyroid hormone receptors (THRs); THRα1 and THRβ1. We aimed to investigate the regulation mechanisms of the THRβ isoform, its association with gene expression changes and implications for cardiac function. Methods: The experiments were performed using adult male mice expressing TRβΔ337T, which contains the Δ337T mutation of the human THRB gene and impairs ligand binding. Cardiac function and RNA expression were studied after hypo-or hyperthyroidism inductions. T3-induced cardiac hypertrophy was not observed in TRβΔ337T mice, showing the fundamental role of THRβ in cardiac hypertrophy. Results: We identified a group of independently regulated THRβ genes, which includes Adrb2, Myh7 and Hcn2 that were normally regulated by T3 in the TRβΔ337T group. However, Adrb1, Myh6 and Atp2a2 were regulated via THRβ. The TRβΔ337T mice exhibited a contractile deficit, decreased ejection fraction and stroke volume, as assessed by echocardiography. In our model, miR-208a and miR-199a may contribute to THRβ-mediated cardiac hypertrophy, as indicated by the absence of T3-regulated ventricular expression in TRβΔ337T mice. Conclusion: THRβ has important role in the regulation of specific mRNA and miRNA in T3-induced cardiac hypertrophic growth and in the alteration of heart functions