RESUMO
The endocannabinoid system is widely expressed throughout the body and is comprised of receptors, ligands, and enzymes that maintain metabolic, immune, and reproductive homeostasis. Increasing interest in the endocannabinoid system has arisen due to these physiologic roles, policy changes leading to more widespread recreational use, and the therapeutic potential of Cannabis and phytocannabinoids. Rodents have been the primary preclinical model of focus due to their relative low cost, short gestational period, genetic manipulation strategies, and gold-standard behavioral tests. However, the potential for lack of clinical translation to non-human primates and humans is high as cross-species comparisons of the endocannabinoid system have not been evaluated. To bridge this gap in knowledge, we evaluate the relative gene expression of 14 canonical and extended endocannabinoid receptors in seven peripheral organs of C57/BL6 mice, Sprague-Dawley rats, and non-human primate rhesus macaques. Notably, we identify species- and organ-specific heterogeneity in endocannabinoid receptor distribution where there is surprisingly limited overlap among the preclinical models. Importantly, we determined there were no receptors with identical expression patterns among mice (three males and two females), rats (six females), and rhesus macaques (four males). Our findings demonstrate a critical, yet previously unappreciated, contributor to challenges of rigor and reproducibility in the cannabinoid field, which has implications in hampering progress in understanding the complexity of the endocannabinoid system and development of cannabinoid-based therapies.
Assuntos
Canabinoides , Endocanabinoides , Masculino , Feminino , Camundongos , Animais , Ratos , Endocanabinoides/metabolismo , Macaca mulatta/metabolismo , Reprodutibilidade dos Testes , Ratos Sprague-Dawley , Canabinoides/metabolismo , Canabinoides/uso terapêutico , Modelos AnimaisRESUMO
The endocannabinoid system is widely expressed throughout the body and is comprised of receptors, ligands, and enzymes that maintain metabolic, immune, and reproductive homeostasis. Increasing interest in the endocannabinoid system has arisen due to these physiologic roles, policy changes leading to more widespread recreational use, and the therapeutic potential of Cannabis and phytocannabinoids. Rodents have been the primary preclinical model of focus due to their relative low cost, short gestational period, genetic manipulation strategies, and gold-standard behavioral tests. However, the potential for lack of clinical translation to non-human primates and humans is high as cross-species comparisons of the endocannabinoid system has not been evaluated. To bridge this gap in knowledge, we evaluate the relative gene expression of 14 canonical and extended endocannabinoid receptors in seven peripheral organs of C57/BL6 mice, Sprague-Dawley rats, and non-human primate rhesus macaques. Notably, we identify species- and organ-specific heterogeneity in endocannabinoid receptor distribution where there is surprisingly limited overlap among the preclinical models. Importantly, we determined there were only five receptors (CB2, GPR18, GPR55, TRPV2, and FAAH) that had identical expression patterns in mice, rats, and rhesus macaques. Our findings demonstrate a critical, yet previously unappreciated, contributor to challenges of rigor and reproducibility in the cannabinoid field, which has profound implications in hampering progress in understanding the complexity of the endocannabinoid system and development of cannabinoid-based therapies.
RESUMO
This study examined the striatal dopamine system integrity and associated behavior in 5- to 7-year-old rhesus monkeys born from mothers that experienced stress and/or consumed moderate levels of alcohol during pregnancy. Thirty-one young adult rhesus monkeys were derived from females randomly assigned to one of four groups: (1) control group that consumed isocaloric sucrose solution throughout gestation; (2) stress group that experienced prenatal stress (10-min removal from home cage and exposure to three random loud noise bursts, gestational days 90 through 145); (3) alcohol group that consumed alcohol (0.6 g/kg/day) throughout gestation; or (4) combined alcohol plus stress group that received both treatments. The subjects were assessed for striatal dopamine system function using positron emission tomography (PET), in which the dopamine (DA)-rich striatum was evaluated in separate scans for the trapping of [(18)F]-Fallypride (FAL) and 6-[(18)F]fluoro-m-tyrosine (FMT) to assess dopamine D2 receptor binding potential (BP) and DA synthesis via dopa decarboxylase activity, respectively. Subjects were previously assessed for non-matching-to-sample (NMS) task acquisition, with ratings of behavioral inhibition, stereotypies, and activity made after each NMS testing session. Subjects from prenatal stress conditions (Groups 2 and 4) showed an increase in the ratio of striatal dopamine D2 receptor BP and DA synthesis compared to controls (Group 1). An increase in the radiotracer distribution volume ratios (DVRs), which is used to evaluate the balance between striatal DA synthesis and receptor availability, respectively, was significantly correlated with less behavioral inhibition. The latter supports a hypothesis linking striatal function to behavioral inhibitory control.
Assuntos
Comportamento Animal/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Dopamina/metabolismo , Etanol/farmacologia , Feto/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico , Análise de Variância , Animais , Animais Recém-Nascidos , Cognição/fisiologia , Feminino , Inibição Psicológica , Macaca mulatta , Masculino , Atividade Motora/efeitos dos fármacos , Gravidez , Distribuição Aleatória , Comportamento Estereotipado/efeitos dos fármacos , Tomografia Computadorizada de Emissão/métodosRESUMO
BACKGROUND: Although high-dose prenatal alcohol exposure is related to cognitive and behavioral impairments in children and adolescents with fetal alcohol syndrome, there is relatively little research on the effects of moderate drinking during pregnancy. We examined learning, memory, and behavior in adolescent rhesus monkeys prenatally exposed to moderate levels of alcohol, psychological stress, or both alcohol and stress. METHODS: Forty adolescent rhesus monkey subjects were derived from four groups of female rhesus monkeys that (1) consumed alcohol throughout gestation; (2) experienced prenatal stress; (3) experienced prenatal stress and alcohol consumption; or (4) control group (no alcohol, no stress). The subjects were assessed for number of trials required to reach 90% criterion of correct responses on nonmatching-to-sample task (NMS), followed by trials with delays of 30, 60, or 120 sec. Ratings of behavior during testing were made after each session. RESULTS: Subjects exposed to moderate prenatal alcohol required significantly more trials to reach criterion on the acquisition phase of the NMS task but had no difficulty with delays. Prenatally stressed monkeys showed lower response inhibition or less behavioral restraint, whereas prenatal alcohol plus stress monkeys showed higher activity level and stereotypies compared with controls. High scores on neonatal measures of orientation (attending to novel stimuli) and motor maturity and low scores on irritability, activity, stereotypies, and impulsivity during acquisition were correlated with fewer trials to criterion on acquisition of NMS. CONCLUSIONS: NMS trials required to reach criterion and behavior during testing are sensitive to moderate-level prenatal alcohol exposure in monkeys. The most adverse behavioral outcomes (hyperactivity and stereotypies) were associated with prenatal alcohol plus stress, raising concerns that environmental stress might provide the context within which fetal alcohol exposure could promote adverse behavioral outcomes. These effects occurred in the absence of either facial deformities or retarded physical growth.
Assuntos
Comportamento Animal/efeitos dos fármacos , Etanol/farmacologia , Aprendizagem/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Animais , Etanol/administração & dosagem , Feminino , Comportamento Impulsivo , Humor Irritável , Macaca mulatta , Atividade Motora , Gravidez , Comportamento Estereotipado , Estresse Fisiológico/complicaçõesRESUMO
BACKGROUND: Moderate prenatal alcohol exposure can contribute to neurodevelopmental deficits in nonhuman primate offspring. The purpose of this study was to examine the effects of gestational timing of alcohol exposure on neurobehavior with a nonhuman primate model. METHODS: Sixty-three rhesus monkey infants (Macaca mulatta), from four groups of females, were assessed: (1) an early alcohol-exposed group, in which mothers voluntarily consumed alcohol on gestational days 0 through 50; (2) a mid to late gestation alcohol-exposed group, in which mothers consumed an identical dose on gestation days 50 through 135; (3) a continuous-exposure group, in which mothers consumed an identical dose on days 0 through 135 or days 0 through 165; and (4) controls, in which mothers voluntarily consumed an isocaloric control solution on gestational days 0 through 50, 50 through 135, 0 through 135, or 0 through 165. Data were obtained on offspring for measures of growth and neurobehavior. RESULTS: There were no effects of alcohol on birthweight, gestation length, or ponderal index. Prenatal exposure to alcohol during early gestation significantly decreased scores on infant neurobehavioral tests overall in multivariate tests, after controlling for birthweight. Univariate tests showed that early gestation alcohol exposure was related to reductions in infant orientation and motor maturity. Mid- to late-gestation exposure also resulted in a reduction in motor maturity but did not affect overall neurobehavioral performance in the multivariate tests. CONCLUSIONS: Early-gestation alcohol exposure is as deleterious to neonatal neurobehavior as late-gestation or continuous exposure. Moreover, neurobehavior seems to be a more sensitive marker of early-gestation moderate alcohol exposure than growth parameters. Women who are attempting to become pregnant should minimize frequent social drinking, because subtle neurodevelopmental effects to the fetus may be induced before pregnancy is detected.
Assuntos
Animais Recém-Nascidos , Etanol/administração & dosagem , Troca Materno-Fetal , Resultado da Gravidez , Animais , Comportamento Animal , Peso ao Nascer , Feminino , Idade Gestacional , Macaca mulatta , Masculino , Comportamento Materno , Atividade Motora , Gravidez , Fatores de TempoRESUMO
In this paper we review three prospective longitudinal studies from our laboratory examining the effects of prenatal stress on early neuro behavior, stress reactivity and learning performance in rhesus monkeys. Either a noise stressor or ACTH treatment was administered to pregnant monkeys during specific periods of pregnancy and offspring were examined repeatedly across development. In all three studies, the prenatally stressed monkeys showed reduced attention and impaired neuromotor functioning during the first month of life compared to controls from undisturbed pregnancies. When the monkeys were separated from their mothers or peers at 6-8 months of age, prenatally stressed monkeys exhibited more disturbance behavior and showed hypothalamic-pituitary-adrenal axis dysregulation. During adolescence, they exhibited impairments in learning, compared to controls.
Assuntos
Comportamento Animal , Aprendizagem , Comportamento Materno , Complicações na Gravidez/etiologia , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/complicações , Fatores Etários , Animais , Ansiedade de Separação/metabolismo , Ansiedade de Separação/psicologia , Atenção , Modelos Animais de Doenças , Feminino , Idade Gestacional , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Macaca mulatta , Atividade Motora , Sistema Hipófise-Suprarrenal/metabolismo , Gravidez , Complicações na Gravidez/psicologia , Estresse Psicológico/psicologiaRESUMO
Developmental ordering is a fundamental prediction of developmental theories and a central issue in developmental research. However, logically sound evidence of developmental ordering is difficult to obtain. This article analyzes the logical basis of testing developmental order hypotheses with categorical measures. Depending on whether saltatory (i.e., discrete) or continuous developmental changes are being assessed, the observed relationship between categorical measures yields very different types of information about developmental ordering. When change is continuous, the relationship between the measures does not confirm any one ordering hypothesis, but rather, disconfirms one or more hypotheses. Whether an underlying variable undergoes saltatory or continuous development has long been recognized as an important theoretical issue, but its impact on the interpretation of developmental ordering has not previously been explicated.
Assuntos
Desenvolvimento Infantil , Cognição , Formação de Conceito , Criança , Interpretação Estatística de Dados , Humanos , Modelos Psicológicos , Projetos de PesquisaRESUMO
BACKGROUND: Violence in the workplace is an ill-defined and underreported concern for health care workers. The objectives of this study were to examine perceived levels of violence in the emergency department, to obtain health care workers' definitions of violence, to determine the effect of violence on health care workers and to determine coping mechanisms and potential preventive strategies. METHODS: A retrospective written survey of all 163 emergency department employees working in 1996 at an urban inner-city tertiary care centre in Vancouver. The survey elicited demographic information, personal definition of violence, severity of violence, degree of stress as a result of violence and estimate of the number of encounters with violence in the workplace in 1996. The authors examined the effects of violence on job performance and job satisfaction, and reviewed coping and potential preventive strategies. RESULTS: Of the 163 staff, 106 (65%) completed the survey. A total of 68% (70/103) reported an increased frequency of violence over time, and 60% (64/106) reported an increased severity. Most of the respondents felt that violence included witnessing verbal abuse (76%) and witnessing physical threats or assaults (86%). Sixty respondents (57%) were physically assaulted in 1996. Overall, 51 respondents (48%) reported impaired job performance for the rest of the shift or the rest of the week after an incident of violence. Seventy-seven respondents (73%) were afraid of patients as a result of violence, almost half (49%) hid their identities from patients, and 78 (74%) had reduced job satisfaction. Over one-fourth of the respondents (27/101) took days off because of violence. Of the 18 respondents no longer working in the emergency department, 12 (67%) reported that they had left the job at least partly owing to violence. Twenty-four-hour security and a workshop on violence prevention strategies were felt to be the most useful potential interventions. Physical exercise, sleep and the company of family and friends were the most frequent coping strategies. INTERPRETATION: Violence in the emergency department is frequent and has a substantial effect on staff well-being and job satisfaction.
Assuntos
Serviço Hospitalar de Emergência , Recursos Humanos em Hospital , Violência/estatística & dados numéricos , Adaptação Psicológica , Adulto , Agressão , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Colúmbia Britânica/epidemiologia , Eficiência , Exercício Físico , Feminino , Hospitais Urbanos , Humanos , Incidência , Relações Interpessoais , Satisfação no Emprego , Masculino , Saúde Ocupacional , Reorganização de Recursos Humanos , Relações Profissional-Paciente , Estudos Retrospectivos , Medidas de Segurança , Sono , Estresse Fisiológico/epidemiologia , Estresse Psicológico/epidemiologia , Violência/prevenção & controle , Local de TrabalhoRESUMO
Two experiments were conducted to investigate the nature of the intuitive problem representation used in evaluating mathematical strategies. The first experiment tested between two representations: a representation composed of principles and an integrated representation. Subjects judged the correctness of unseen math strategies based only on the answers they produced for a set of temperature mixture problems. The distance of the given answers from the correct answers and whether the answers violated one of the principles of temperature mixture were manipulated. The results supported the principle representation hypothesis. In the second experiment we manipulated subjects' understanding of an acid mixture task with a brief paragraph of instruction on one of the principles. Subjects then completed an estimation task intended to measure their understanding of the problem domain. The evaluation task from the first experiment was then presented, but with acid mixture instead of temperature mixture. The results showed that intuitive understanding of the domain mediates the effect of instruction on evaluating problems. Additionally, the results supported the hypothesis that subjects perform a mapping process between their intuitive understanding and math strategies.
Assuntos
Intuição/fisiologia , Aprendizagem/fisiologia , Lógica , Matemática , Resolução de Problemas/fisiologia , Análise de Variância , Humanos , Modelos PsicológicosRESUMO
The purpose of this research was to investigate moral reasoning related to sexual behavior that could lead to the transmission of sexually transmitted diseases (STDs). Using hypothetical dilemmas about situations in which STDs can be transmitted, respondents were asked to explain why they believed the characters should or should not engage in risky behaviors. 40 college freshmen (M = 18.3 years) and 32 college seniors (M = 22.3 years) participated. Using Kohlberg's moral stage theory and Gilligan's moral orientation model, the interviews were scored for moral stage and moral orientation. Results indicated that the older age group had a significantly higher stage of moral reasoning than the younger age group when responding to dilemmas about STDs. There was a significant difference in moral stage between dilemmas, reflecting the possible effect of dilemma content on moral reasoning. The overall pattern of results shows nonsignificant gender differences in stage of moral reasoning and moral orientation. Clinical and theoretical implications of these findings for understanding the role of moral reasoning in sexual risky behavior are discussed.
Assuntos
Atitude Frente a Saúde , Princípios Morais , Infecções Sexualmente Transmissíveis/psicologia , Adolescente , Adulto , Feminino , Identidade de Gênero , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Determinação da Personalidade , Infecções Sexualmente Transmissíveis/transmissãoRESUMO
Measurement issues surrounding the quantification of subjective states such as sensations and attitudes have received increasing attention in nursing in recent years. It has sometimes been argued that magnitude estimation (ME) procedures are superior to category rating (CR) methods for scaling of subjective states which require judgments of intensity or strength of perception. A critique of the two scaling methods is presented. In contrast to arguments first proposed by Stevens and others for the superiority of ME procedures and the ability to attain "direct" ratio level measurement with ME scaling, there is evidence to suggest that ME procedures do not in fact produce ratio level scales. The "characteristic" exponents associated with ME scaling are not necessarily intrinsic to particular subjective states. CR scales neither necessarily constrain nor lack the requisite sensitivity needed to produce valid responses. It is concluded that ME is not necessarily superior to the commonly used CR method for scaling of subjective states in nursing research. Implications of the controversy for selection of scaling methods for nursing research are discussed. Greater attention to the ordinal or rank-order properties of data is encouraged. A small set of data is used to illustrate the importance of rank order properties in scaling subjective states in nursing.
Assuntos
Atitude , Pesquisa em Enfermagem/métodos , Percepção , Testes Psicológicos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , PsicometriaRESUMO
In the present study college student (N = 186) made judgments of the likelihood of accepting a medication for treatment of a hypothetically experienced clinical depression. Three types of information were manipulated: effectiveness of the medication for alleviating the symptoms of depression, potential side effects of the medication, and severity of depression hypothetically being experienced. The functional-measurement approach was used to examine whether self-reports are related to judgments and whether there is configurality in judging likelihood of medication acceptance. The results showed that subjects who reported different variables to be most important had predictably different effects of the variables in their judgments. There was also evidence for configural combination of information, and the nature of the configurality differed between subjects who reported Depression versus Side Effects as the most important type of information, respectively. The results show how the same information can be used differently by different individuals in making judgments, and that self-reports may reveal some important aspects of how information is used. The implications of the individual differences for health care consumer decision making and health care professionals' assessments and interventions are discussed.
Assuntos
Tomada de Decisões , Transtorno Depressivo/tratamento farmacológico , Julgamento , Processos Mentais , Aceitação pelo Paciente de Cuidados de Saúde , Feminino , Humanos , Funções Verossimilhança , Masculino , Modelos Psicológicos , Educação de Pacientes como Assunto , Índice de Gravidade de Doença , Resultado do TratamentoAssuntos
Calcitonina/sangue , Lesão por Inalação de Fumaça/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Cálcio/sangue , Humanos , Soros Imunes , Pulmão/metabolismo , Pessoa de Meia-Idade , Sistemas Neurossecretores/metabolismo , Albumina Sérica , Lesão por Inalação de Fumaça/mortalidadeRESUMO
The need for refresher courses is a constant, as is the lack of courses, faculty, and geographically sufficient numbers of students. This article describes an approach that North Carolina nurses developed to address the need for RN refresher programs.
Assuntos
Currículo , Educação Continuada em Enfermagem/métodos , Capacitação em Serviço/métodos , Instruções Programadas como Assunto , Humanos , North Carolina , Projetos PilotoRESUMO
One of the principal causes of death from burns is inhalation injury. The pulmonary neuroendocrine cell contains and secretes immunoreactive calcitonin (iCT), and, under the influence of various irritative stimuli, can be induced to secrete iCT in excess. A prospective study of serum iCT levels in 41 patients with burns was undertaken. Mean serum iCT levels were four times normal values at the time of admission and reached 31 times normal values by 24 hours after injury. These levels did not correlate specifically with burn size. However, serum iCT had a very strong positive correlation with mortality, and in addition, was highest in patients who died early after injury compared with those who died late after injury. Patients who were clinically suspected to have pulmonary injury and who died had markedly higher levels of iCT than those who survived. In addition, serum iCT correlated positively with the need for mechanical ventilation and the amount of pulmonary shunting. Although other factors may also play a role in hypercalcitoninemia, serum iCT may be an important marker for the presence of inhalation injury, as well as a prognostic indicator.
Assuntos
Queimaduras por Inalação/diagnóstico , Calcitonina/sangue , Adulto , Biomarcadores/sangue , Nitrogênio da Ureia Sanguínea , Queimaduras por Inalação/sangue , Queimaduras por Inalação/mortalidade , Cálcio/sangue , Creatinina/sangue , Feminino , Humanos , Pulmão/metabolismo , Masculino , Sistemas Neurossecretores/metabolismo , Fosfatos/sangue , Estudos Prospectivos , Radioimunoensaio , Albumina Sérica/análiseRESUMO
The molecular heterogeneity of serum immunoreactive calcitonin (iCT) was analyzed from a prospective study of 41 burn patients. Using different region-specific anticalcitonin antisera, the ratio of mid-region-recognizing to carboxyl terminal-region-recognizing iCT was found to increase acutely in those who subsequently died. The highest ratios occurred in those who died early of respiratory complications. Sephadex chromatography and reversed-phase HPLC demonstrated that the serum iCT circulated predominantly in the large molecular mass prohormone form (16 kDa). In comparison, iCT of normal human lung and of normal thyroid was shown to consist primarily of smaller monomeric mass forms. Furthermore, in 12 normal volunteers who were evaluated with a calcium-pentagastrin infusion, the ratio of iCT levels did not differ from the baseline ratio despite a 50% increase in serum iCT. These results suggest that in burns, the inhalational injury-associated hypercalcitonemia is characterized by a preferential release of procalcitonin; a form of constitutive secretion. The measurement of serum procalcitonin levels would appear to be a useful prognostic indicator of the severity of inhalational injury occurring in burn patients.
Assuntos
Queimaduras por Inalação/sangue , Calcitonina/sangue , Precursores de Proteínas/sangue , Biomarcadores , Peptídeo Relacionado com Gene de Calcitonina , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Humanos , Prognóstico , RadioimunoensaioRESUMO
2 separate aspects of perspective taking are that judgments attributed to another should depend on the information available to the other (Information effect) and on how the other's use of information differs from one's own (Weighting effect). These 2 aspects of perspective taking were studied in a moral judgment task with preschoolers, and second and fifth graders. Subjects were read a series of stories about a little boy transgressing and asked to make judgments from both their own perspective and that of a mother character in the stories. The mother story character had either the same information as the subject or only partial information. Valence of intention and consequence and the amount of mother's knowledge varied factorially. Subjects were clustered using scores derived from the judgements. 3 clusters were found that showed different levels of perspective-taking ability. There was a developmental progression in the 3 levels of perspective taking. Subjects in the Harshness cluster attributed harsher judgments to the mother perspective. Subjects in the Weighting cluster weighted information differently depending on the perspective from which they judged. Subjects in the Information-and-Weighting cluster weighted information differently depending on perspective, and also considered the amount of information available to the mother character in attributing judgments. The findings are compared to current theory on the development of perspective taking. Future research and theory need to consider the influence of both information and weighting differences on performance in perspective-taking tasks.
Assuntos
Afeto , Desenvolvimento Infantil , Formação de Conceito , Julgamento , Relações Mãe-Filho , Reconhecimento Visual de Modelos , Criança , Pré-Escolar , Expressão Facial , Feminino , Humanos , Individualidade , Masculino , SocializaçãoRESUMO
In pregnant hamsters, three transplacental injections of the ganglionic agonist nicotine resulted in a dose-dependent decrease in the concentration of mammalian bombesin (MB) in the lungs of neonatal (1 day old) animals. This decrease in neonatal MB did not occur if nicotine was given only once during gestation, or when it was given three times in conjunction with the ganglionic antagonist mecamylamine. In one week old animals born of mothers who had been exposed to three doses of nicotine during gestation, lung MB had returned to control levels. When nicotine was injected into neonatal animals, lung MB acutely increased. Right sided vagotomy to young hamsters resulted in an increase in the ratio of lung MB (right vs. left lobe) 1 week after surgery. Administration of nicotine to vagotomized animals resulted in decreased total lung MB and normalization of the MB ratio. Thus, nicotine has a potent modulatory influence on lung MB during fetal and neonatal development and maturation. This influence is also present in young animals that are subjected to partial denervation. Our hypothesis is that the innervation of pulmonary neuroendocrine (PNE) cells influences both PNE cell growth and its synthetic function. PNE MB, which is an epithelial and neoplastic growth factor, may play a role in this response.
Assuntos
Bombesina/metabolismo , Pulmão/metabolismo , Neuroimunomodulação/efeitos dos fármacos , Nicotina/farmacologia , Animais , Animais Recém-Nascidos , Cricetinae , Feminino , Pulmão/efeitos dos fármacos , Masculino , Troca Materno-Fetal/efeitos dos fármacos , Mesocricetus , Sistemas Neurossecretores/efeitos dos fármacos , Sistemas Neurossecretores/metabolismo , Gravidez , VagotomiaRESUMO
The synthetic progestin medroxyprogesterone acetate (MPA) has previously been shown to be an inducer of hepatic microsomal cytochrome P-450 in both man and the rat. We have assessed the ability of a variety of oral doses of MPA to induce either hepatic cytochrome P-450 as measured by antipyrine clearance or alpha 1-acid glycoprotein (AGP) in beagle dogs. Over the range of 25 mg/d to 400 mg/d, MPA did not induce antipyrine clearance. The concentration of AGP only increased at the 400 mg/d level, and was effected to a much smaller extent than has been previously observed for other inducing agents. MPA was also tested as a promoter of induction by combining it with a course of rifampin capable of substantially elevating both antipyrine clearance and AGP. MPA was without effect. The results of these experiments are discussed in light of the toxicology of MPA in beagles.