RESUMEN
Spontaneous prostatic hyperplasia in the beagle appears to progress with age from a glandular to a cystic histological appearance. Prostatic hyperplasia can be induced in young beagles with intact testes by treatment for 4 mo with either dihydrotestosterone or 5 alpha-androstane-3 alpha, 17 beta-diol, alone, or with either of these steroids in combination with 17 beta-estradiol. In contrast, the induction of prostatic hyperplasia in young castrated beagles, in which the gland had been allowed to involute for 1 mo, requires the administration of both 17 beta-estradiol and either 5 alpha-androstane-3 alpha, 17 beta-diol or dihydrotestosterone. Testosterone and 17 beta-estradiol, either singly or in combination, did not produce the hyperplastic condition in intact or castrated beagles. The experimentally induced prostatic hyperplasia is identical in pathology to the glandular hyperplasia that occurs naturally in the aging dog with intact testes. However, cystic hyperplasia was not produced by any of the treatments tested in young animals.
Asunto(s)
Enfermedades de los Perros/etiología , Hiperplasia Prostática/etiología , Androstano-3,17-diol/administración & dosificación , Animales , Castración , Dihidrotestosterona/administración & dosificación , Enfermedades de los Perros/patología , Perros , Estradiol/administración & dosificación , Masculino , Tamaño de los Órganos/efectos de los fármacos , Próstata/patología , Hiperplasia Prostática/patología , Hiperplasia Prostática/veterinaria , Testículo/fisiología , Testosterona/administración & dosificaciónRESUMEN
This paper is a cross-sectional study of spontaneous benign prostatic hyperplasia (BPH) in a single canine species. The effects of aging and hormonal changes on the growth, histology, and glandular secretory function of the canine prostate were studied in 42 male beagles ranging in age from 8 mo to 9 yr. The beagle prostate enlarges for at least 6 yr, whether normal or hyperplastic. In contrast, prostatic secretory function, determined by ejaculate volume and total ejaculate protein, declines markedly after 4 yr of age. These reciprocal growth and functional changes in the prostate are closely associated with a progressive increase in the incidence of BPH, which is already apparent in some dogs by age two. With age there is a modest decrease in serum androgen levels with no apparent change in serum 17 beta-estradiol levels. This suggests that the growth and functional changes that are associated with the development of BPH and are initiated very early in life reflect an altered sensitivity of the prostate to serum androgens or a response to the relative decrease in the serum androgen to estrogen ratio.
Asunto(s)
Andrógenos/sangre , Enfermedades de los Perros/fisiopatología , Estradiol/sangre , Próstata/fisiopatología , Hiperplasia Prostática/veterinaria , Envejecimiento , Animales , Modelos Animales de Enfermedad , Perros , Masculino , Tamaño de los Órganos , Próstata/patología , Hiperplasia Prostática/patología , Hiperplasia Prostática/fisiopatología , Recuento de EspermatozoidesRESUMEN
The present study was designed to evaluate the role of thromboxane in radiation-induced cutaneous injury and to use the quantitation of cutaneous thromboxane B2 as an indicator of vascular alteration and tissue viability in canine skin. Ten adult intact male dogs underwent epithermal neutron irradiation with or without boron neutron capture. Skin biopsies were obtained from (1) within, (2) the edge of, and (3) outside the radiation field at 5, 8, 11, 14, 21, and 90 days after irradiation. Clinical changes at each sampling time were assigned a numerical score. One-half of each biopsy was assigned a numerical score based on histologic changes. Thromboxane B2 was measured from the second half by enzyme immunoabsorbent assay. Thromboxane B2 concentration paralleled the response of clinical and histologic score over time, indicating the value of thromboxane measurement for evaluation of skin changes secondary to irradiation.
Asunto(s)
Traumatismos Experimentales por Radiación/metabolismo , Piel/efectos de la radiación , Tromboxano B2/análisis , Animales , Terapia por Captura de Neutrón de Boro , Perros , Masculino , Piel/irrigación sanguínea , Piel/químicaRESUMEN
The effect of 50 ug/kg prostaglandin F2a (PGF2a) was compared with 250 ug/kg PGF2a on uterine motility in the diestrous female. Microtipped pressure transducers were surgically implanted in the uteri of 6 females at 30 days diestrus and in 6 females at 60 days diestrus. Uterine responses to intravenous PGF2a (5 ug/kg), oxytocin (0.05 USP units/kg), and intramuscular PGF2a (50 ug/kg and 250 ug/kg) were measured in the awake females on Days 1 and 2 after implantation. There was no significant difference in the increase in intrauterine pressure produced by 50 ug/kg of PGF2a compared with 250 ug/kg of PGF2a. The longest duration of the effect occurred when 250 ug/kg of PGF2a were given. Side effects were also documented. Significantly more vomiting occurred when 250 ug/kg PGF2a were given than when 50 ug/kg PGF2a were administered. The only advantage to using a higher dosage of PGF2a appears to be the longer duration of motility.
RESUMEN
The effect of xylazine on intrauterine pressure was compared to that of prostaglandin and oxytocin in seven diestrual bitches. Microtipped pressure transducers were surgically implanted in the uteri of four bitches at 30 d diestrus and in three bitches at 60 d diestrus. Uterine contractile force was measured in the awake bitches on Day 1 and Day 2 following implantation. Uterine responses to intravenous prostaglandin (5 mug/kg), oxytocin (0.05 USP units/kg), and xylazine (0.22 mg/kg) were measured. In the 30-d diestrual bitches, prostaglandin and oxytocin increased intrauterine pressure to 67 and 69 mmHg, with the duration of action being 16 and 14 min, respectively. Xylazine increased intra-uterine pressure to 49 mmHg and had a duration of action of 8 min. All results were decreased but similar in the 60-d diestrual bitches. These findings indicate that xylazine, given intravenously, produces a transitory increase in intrauterine pressure in the diestrual bitch.
RESUMEN
Effects of beta-endorphin and naloxone on bovine uterine motility were tested both in vivo and in vitro. Six cyclic Holstein cows were used to study in vivo effects of beta-endorphin and naloxone on uterine motility during estrus and diestrus. Intrauterine pressure changes were recorded by a microtip pressure transducer before and after treatment. Blood samples were taken every 10 min during the recording periods for beta-endorphin assay. The results revealed that beta-endorphin anc naloxone had no effect on intrauterine pressure in vivo. The effects of beta-endorphin and naloxone on myometrial contractility were also examined in vitro. Beta-endorphin and naloxone were added to tissue baths containing estrous and diestrous uterine strips. The results showed no significant effect of beta-endorphin and naloxone on bovine myometrial contractility. The role of beta-endorphin in bovine reproductive physiology is still not clearly understood, and additional studies are needed.
RESUMEN
To evaluate the use of technetium pertechnetate (99mTcO4) as a means of estimating gastric mucosal integrity, nuclear images of the empty stomach were obtained from 6 dogs at 20, 40, 60, 120, 180, and 240 minutes after IV administration of the radiopharmaceutical. Blood and gastric secretion samples were collected during the same time intervals. The left lateral-view image of the stomach was used to calculate the relative fraction of the dose in the stomach and the count density ratio. Between 20 and 40 minutes and 40 and 60 minutes, significant differences (P less than 0.001) were apparent in the amount of 99mTcO4 in the stomach. Blood concentration of 99mTcO4 decreased significantly (P less than 0.001), whereas gastric secretion concentration increased significantly (P less than 0.001) over time. Qualitative assessment of the gastric nuclear scans and the statistical analytic results indicated that the optimal time for imaging the canine stomach was between 40 and 60 minutes after radiopharmaceutical administration. In a second study, the same dogs were pretreated with the H2-receptor antagonist cimetidine and the cholinergic antagonist glycopyrrolate to block gastric secretions. Over time, changes in the relative dose fraction in the stomach and the density ratio were the same as values obtained during the experiment performed without use of cimetidine and glycopyrrolate. Results of the study indicate that nuclear imaging with 99mTcO4 outlines normal canine gastric mucosa and that pretreatment with cimetidine and glycopyrrolate has no effect on the quality of the gastric image.
Asunto(s)
Perros/anatomía & histología , Mucosa Gástrica/diagnóstico por imagen , Animales , Cimetidina/farmacología , Jugo Gástrico/química , Jugo Gástrico/efectos de los fármacos , Jugo Gástrico/metabolismo , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/metabolismo , Glicopirrolato/farmacología , Análisis Multivariante , Cintigrafía , Pertecnetato de Sodio Tc 99m/sangre , Pertecnetato de Sodio Tc 99m/farmacocinéticaRESUMEN
A nuclear imaging technique of the stomach, using technetium pertechnetate (99mTcO4), was evaluated in healthy dogs. The stomach was first insufflated with room air, then filled with barium sulfate to induce mild distention, outlining the gastric wall. Six dogs were imaged twice: initially without use of drugs that might affect gastric secretion of 99mTcO4, then after pretreatment with cimetidine and glycopyrrolate. These scans established the appearance of the normal (control) stomach and compared the quality of the image in the same dogs not pretreated, then pretreated with cimetidine and glycopyrrolate before administration of 99mTcO4. Avascular defects were then surgically created on the greater curvature of the stomach of the same 6 dogs, and gastroscintigraphy was performed in similar manner. Significant (P less than 0.05) quantitative differences were detected in the gastric images for scans of the avascular area, compared with various control scans. Qualitative assessment had overall accuracy of 90.28%. Results of the study reported here indicate that nuclear imaging can be a valuable diagnostic technique for detecting ischemic areas in the gastric wall of dogs.
Asunto(s)
Enfermedades de los Perros/diagnóstico por imagen , Isquemia/veterinaria , Estómago/irrigación sanguínea , Animales , Diagnóstico por Computador , Perros , Isquemia/diagnóstico por imagen , Análisis Multivariante , Valor Predictivo de las Pruebas , Cintigrafía , Pertecnetato de Sodio Tc 99m , Estómago/diagnóstico por imagenRESUMEN
The seminal volume of young adult Beagles was correlated with the size of and disease in their prostates. The ejaculate volume of naturally collected semen increased in a linear manner with prostatic weight in dogs with normal or glandular hyperplastic prostates. This correlation was not observed in the dogs with cystic hyperplasia, in which there was a reduction in volume of 50% in the semen produced for each gram of prostate. There were no significant differences in other seminal characteristics regardless of prostatic size of disease.
Asunto(s)
Enfermedades de los Perros/fisiopatología , Próstata/patología , Hiperplasia Prostática/veterinaria , Semen/fisiología , Animales , Enfermedades de los Perros/patología , Perros , Masculino , Tamaño de los Órganos , Hiperplasia Prostática/patología , Hiperplasia Prostática/fisiopatologíaRESUMEN
Natural and drug-induced uterine motilities (UM) were recorded via uterine-implanted catheter-tip pressure transducers in 5 bitches during proestrus and estrus and in 6 bitches during early (30 days) and late (60 days) diestrus. The UM was monitored in unanesthetized bitches for 2 days after the estrous-cycle stage had been determined by vaginal cytologic findings. Natural UM, expressed as Alexandria units (pressure X frequency X duration of contractions), was greatest during estrus, moderate during proestrus, and appreciably decreased or lacking during early and late diestrus. During proestrus and estrus, prostaglandin F2 alpha (5 micrograms/kg of body weight, IV) induced intrauterine pressures of 107 and 115 mm of Hg, respectively, and oxytocin (0.05 USP units/kg, IV) induced pressures of 106 and 116 mm of Hg, respectively. In contrast, the intrauterine pressure values induced by prostaglandin F2 alpha given IV during early and late diestrus were 61 and 58 mm of Hg, respectively, and for oxytocin, were 61 and 51 mm of Hg, respectively. Prostaglandin F2 alpha given IM (50 micrograms/kg) also induced a greater intrauterine pressure during proestrus and estrus than during diestrus. We concluded that in the bitch, natural and drug-induced UM are decreased during early and late diestrus.
Asunto(s)
Perros/fisiología , Estro/fisiología , Contracción Uterina , Animales , Diestro/fisiología , Dinoprost , Femenino , Oxitocina/farmacología , Proestro/fisiología , Prostaglandinas F/farmacología , Contracción Uterina/efectos de los fármacosRESUMEN
Spontaneous and drug-induced uterine motility (UM) was recorded in 5 nonanesthetized bitches for 2 to 4 days. Catheter-tip pressure transducers were surgically implanted in 1 uterine horn, tunneled subcutaneously to exit from the skin over the dorsal lumbar area, and protected by a bandage. On the day after implantation, spontaneous UM was recorded in the awake bitch. Effects of IV prostaglandin (PG) F2 alpha (5 micrograms/kg of body weight) and oxytocin (0.05 USP U/kg) and IM PGF2 alpha (25 micrograms/kg) were measured. Estradiol (1 to 25 micrograms/kg) was administered and the study was repeated 24 hours later. In awake bitches, spontaneous UM was 190% greater than UM in anesthetized bitches. Uterine motility was increased by more than 100% after IV PGF2 alpha or oxytocin and by 52% after IM PGF2 alpha. Estradiol abolished spontaneous UM, but did not affect drug-induced responses. Seemingly, spontaneous and drug-induced UM can be documented in the nonanesthetized bitch.
Asunto(s)
Perros/fisiología , Contracción Uterina , Animales , Estradiol/análogos & derivados , Estradiol/farmacología , Femenino , Oxitocina/farmacología , Prostaglandinas F/farmacología , Distribución Aleatoria , Contracción Uterina/efectos de los fármacosRESUMEN
A granulosa cell tumor was found in a dog with clinical signs of persistent estrus that began 6 years after ovariohysterectomy had been performed. The tumor was diagnosed by use of ultrasonography, provocative testing with human chorionic gonadotropin, and exploratory laparotomy. Hyperestrogenism from functional tumor cells caused bone marrow suppression and endocrine alopecia. Successful treatment included tumor removal, blood transfusions, and antibiotic administration.
Asunto(s)
Enfermedades de los Perros/diagnóstico , Tumor de Células de la Granulosa/veterinaria , Neoplasias Ováricas/veterinaria , Animales , Gonadotropina Coriónica , Enfermedades de los Perros/etiología , Enfermedades de los Perros/cirugía , Perros , Estradiol/sangre , Femenino , Tumor de Células de la Granulosa/diagnóstico , Tumor de Células de la Granulosa/etiología , Tumor de Células de la Granulosa/cirugía , Histerectomía/veterinaria , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/etiología , Neoplasias Ováricas/cirugía , Ovariectomía/veterinaria , Complicaciones Posoperatorias/veterinaria , Progesterona/sangre , Reoperación/veterinariaRESUMEN
Saphenous nerve biopsy was performed to diagnose globoid cell leukodystrophy in a 3-month-old West Highland White Terrier. The dog had progressive neurologic disease that appeared to involve the cerebellum, spinal cord, and lower motor neurons to the hind limbs. Light and transmission electron microscopic findings of the nerve biopsy specimen established the diagnosis. Peripheral nerve biopsy may provide a reliable antemortem method for diagnosis of globoid cell leukodystrophy.
Asunto(s)
Enfermedades de los Perros/diagnóstico , Leucodistrofia de Células Globoides/veterinaria , Nervios Periféricos/patología , Animales , Biopsia/veterinaria , Diagnóstico Diferencial , Enfermedades de los Perros/genética , Enfermedades de los Perros/patología , Perros , Femenino , Leucodistrofia de Células Globoides/diagnóstico , Leucodistrofia de Células Globoides/genética , Leucodistrofia de Células Globoides/patología , Microscopía Electrónica , Nervios Periféricos/ultraestructuraRESUMEN
Pharyngeal polyps were diagnosed in 2 sibling kittens referred for evaluation of chronic upper respiratory tract disease. Surgical excision of the masses was performed in both kittens after skull radiography and oral examination. One kitten had a recurrence of pharyngeal polyps 5 weeks after surgery and was euthanatized and necropsied. The clinical and histologic findings in these 2 cases suggested a congenital origin of this disease.
Asunto(s)
Enfermedades de los Gatos/genética , Neoplasias Faríngeas/veterinaria , Pólipos/veterinaria , Animales , Enfermedades de los Gatos/cirugía , Gatos , Femenino , Neoplasias Faríngeas/genética , Neoplasias Faríngeas/cirugía , Pólipos/genética , Pólipos/cirugíaRESUMEN
Papillary squamous cell carcinomas were located on the gingiva of 3 young dogs. The tumors locally invaded the soft tissues of each dog, and invaded bone in 2 dogs. Surgical excision was unsuccessful in eliminating 2 of the tumors. Surgery and radiotherapy were effective, and recurrence has not been observed in 39 months in 1 dog, 32 months in a second, and 10 months in a third. Superficially, the oral masses resembled papillomas, which are known to be caused by viruses. Cytopathologic indication of productive infection was not evident, and papillomavirus antigens could not be detected by immunohistochemical methods. Electron microscopy failed to identify viral particles in 2 of the tumors. High and low molecular weight DNA extracts from 2 of the tumors contained no detectable papillomavirus genome when probed under conditions of either high or low stringency by Southern blot hybridization with a cloned canine oral papillomavirus genome.